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61.
F. MONTEALEGRE‐Z 《Journal of evolutionary biology》2009,22(2):355-366
Male katydids (Orthoptera: Tettigoniidae) produce mating calls by rubbing the wings together, using specialized structures in their forewings (stridulatory file, scraper and mirror). A large proportion of species (ca. 66%) reported in the literature produces ultrasonic signals as principal output. Relationships among body size, generator structures and the acoustic parameters carrier frequency (fc) and pulse duration (pd), were studied in 58 tropical species that use pure‐tone signals. A comparative analysis, based on the only available katydid phylogeny, shows how changes in sound generator form are related to changes in fc and pd. Anatomical changes of the sound generator that might have been selected via fc and pd are mirror size, file length and number of file teeth. Selection for structures of the stridulatory apparatus that enhance wing mechanics via file‐teeth and scraper morphology was crucial in the evolution of ultrasonic signals in the family Tettigoniidae. 相似文献
62.
Contrary to theoretical predictions, female 2‐spot ladybirds (Adalia bipunctata) mate many more times than necessary to maintain high fertilisation success and may gain through the acquisition of material or genetic benefits. In order to investigate this mating system in detail, microsatellite markers have been isolated using a modified enrichment technique. Thirty‐nine loci were successfully amplified by polymerase chain reaction (PCR), of which only two were monomorphic. Detailed characterization of ten loci revealed very high levels of polymorphism. These markers are likely to be invaluable tools with which to study population genetics and patterns of paternity in this species. 相似文献
63.
This paper examines family resemblance for five anthropometric measurements (height, weight, triceps skinfold, upper arm circumference relaxed [UACR] and flexed [UACF] and for systolic and diastolic blood pressure in a group of adult Caribbean islanders of primarily African ancestry. Six hypotheses about family resemblance are tested by using path analysis and likelihood ratios. Significant intergenerational transmission is found only for height and UACR. For weight, UACF, and diastolic blood pressure, non-transmissible sibling resemblance is the primary component of family resemblance, although significant marital resemblance exists for diastolic blood pressure. Triceps skinfold and systolic blood pressure show no evidence of any family resemblance. Although results for highly heritable traits such as height are comparable to reports from other populations, measurements with a large contribution from common family environment or residual environmental effects, such as triceps skinfold or blood pressure, have much lower family resemblance in this population than in other populations. We hypothesize that this difference is due to the fact that adult children and their parents do not share a common household in this culture and to the presence of major nonfamilial environmental factors contributing to obesity and hypertension in this population. 相似文献
64.
L B Flander 《American journal of physical anthropology》1978,49(1):103-110
Metric data on 200 sacra of known sex, age and race are analyzed to determine the usefulness of conventional observations for determining sex in this bone. Results of the univariate analysis show that significant sex differences in the sacrum involve primarily the top portion of the bone for both whites and blacks. However, measurements of curvature are important sex differences in the sample of blacks. A new index relating the S1 body to sacral breadth is proposed as more useful in classifying the bones by sex than indices involving other measurements. Discriminant analysis shows that the sample of whites can be analyzed significantly better by this method than by using an index. The choice of univariate or multivariate method must depend on the condition of the bone, and will be influenced to some extent by the race from which the sample is drawn. 相似文献
65.
Laryngeal air sacs are circular out-pocketings, located in the hyoid bone with their ostium in the midline of the anterior part of the larynx. From previous cadaver studies of the rhesus monkey it was deduced that the function of the air sac is to act as a resonating chamber. The present study was designed to test this hypothesis. Recordings were made of three rhesus monkeys before and after surgical removal of the air sac. Spectrographic analysis of the monkeys' vocalizations indicated that differences in formant frequency characteristics between pre-and post-surgical recordings were negligible. This finding suggests that the laryngeal air sac does not play an important role in the resonant properties of the monkeys' vocal tracts. 相似文献
66.
Akinbo A. Adesomoju Joseph I. Okogun Michael P. Cava Patrick J. Carroll 《Phytochemistry》1983,22(11):2535-2536
A tricyclic diterpene ketone, roseadione, has been isolated from Hypoestes rosea and its structure established as a dicyclopenta[a, d]cyclo 相似文献
67.
Jennifer F Biddle James Robert White Andreas P Teske Christopher H House 《The ISME journal》2011,5(6):1038-1047
The Brazos-Trinity Basin on the slope of the Gulf of Mexico passive margin was drilled during Integrated Ocean Drilling Progam Expedition 308. The buried anaerobic sediments of this basin are largely organic-poor and have few microbial inhabitants compared with the organic-rich sediments with high cell counts from the Peru Margin that were drilled during Ocean Drilling Program Leg 201. Nucleic acids were extracted from Brazos-Trinity Basin sediments and were subjected to whole-genome amplification and pyrosequencing. A comparison of the Brazos-Trinity Basin metagenome, consisting of 105 Mbp, and the existing Peru Margin metagenome revealed trends linking gene content, phylogenetic content, geological location and geochemical regime. The major microbial groups (Proteobacteria, Firmicutes, Euryarchaeota and Chloroflexi) occur consistently throughout all samples, yet their shifting abundances allow for discrimination between samples. The cluster of orthologous groups category abundances for some classes of genes are correlated with geochemical factors, such as the level of ammonia. Here we describe the sediment metagenome from the oligotrophic Brazos-Trinity Basin (Site 1320) and show similarities and differences with the dataset from the Pacific Peru Margin (Site 1229) and other pyrosequenced datasets. The microbial community found at Integrated Ocean Drilling Program Site 1320 likely represents the subsurface microbial inhabitants of turbiditic slopes that lack substantial upwelling. 相似文献
68.
Selective inhibition of carbonic anhydrase (CA) enzyme is an active area of research for medicinal chemists. In the current account, a hybrid pharmacophore approach was employed to design sulfonamide, amide and amine containing new series of potent carbonic anhydrase II inhibitors. The aromatic fragment associated with pharmacophore was altered suitably in order to find effective inhibitors of CA-II. All the derivatives 4a-4m showed better inhibition compared to the standard acetazolamide. In particular, compound 4l exhibited significant inhibition with IC50 value of 0.01796 ± 0.00036 µM. The chemo-informatics analysis justified that all the designed compounds possess <10 HBA and <5 HBD. The ligands-protein binding analyses showed that 4l confined in the active binding pocket with three hydrogen bonds observed with His63, Asn66 and Thr197 residues. 相似文献
69.
Abstract. Growth rates throughout an organ curving phototropically under continuous, unilateral while light were monitored by lime-lapse photography of cress hypocotyls marked into 1 mm sections by two rows of ion-exchange beads. Curvature resulted from an integrated sequence of changes in growth rate on each side of the organ, but the actual patterns of change and, therefore rales of curvature, differed within even this one species, depending upon the immediate pretreatment of the seedlings. Transference of seedlings from darkness to unilateral irradiation gave immediate growth inhibition on both sides of the organ. Curvature resulted from differential recovery of growth rate, being seen first on the shaded side, most prominently in the apical regions; only 2h after initial exposure to light did growth recover on the lit (lower) side. On the other hand, transfer of seedlings from omnilateral to unilateral irradiation of the same intensity resulted in simultaneous growth inhibition on the irradiated side and stimulated growth on the shaded side: this growth stimulation of the shaded side was greater than occurred in totally darkened control plants. 相似文献
70.
H. Hecker 《Biometrical journal. Biometrische Zeitschrift》1987,29(7):763-770
It is shown that in some experimental designs the MANOVA- and the GMANOVA-model are too restrictive either to yield all hypothesis tests of interest or to reflect all known features of the design. An extension of these models is derived by relating the response vectors with the unknown model parameters by linear equations which may be completely different for each of the p components of the response vector and for each of the n independent vectors. For situations, in which a Wishart-distributed estimator for the underlying common covariance matrix is attainable, a test for any s-dimensional linear hypothesis on the model parameters is derived. 相似文献