RELATIONSHIP OF SPATIAL DENSITY OF SPRAY DROPLET TO FREQUENCY OF CONTACT BY EUROPEAN RED MITE (ACARINA: TETRANYCHIDAE)

1973 ◽  
Vol 105 (7) ◽  
pp. 999-1001
Author(s):  
R. W. Fisher ◽  
D. R. Menzies
Keyword(s):  
Adult Female ◽  
Spatial Density ◽  
Spray Droplet ◽  
Leaf Discs ◽  
European Red Mite ◽  
Frequency Of Contact ◽  
Relationship Of ◽  
The Relationship ◽  
Individual Adult

AbstractThe behaviour of individual adult female European red mites was observed on peach leaf discs sprayed with different numbers of 200 micron droplets of nigrosine dye solution, nigrosine plus Carzol miticide, and nigrosine plus dicofol. On nigrosine and Carzol deposits, the relationship between the number of contacts and the number of stains was linear, but the addition of Carzol reduced the slope of the line. Tests of stains containing dicofol were intermediate to those of nigrosine and Carzol.

Community Lost or Transformed? Urbanization and Social Ties

2003 ◽  
Vol 2 (3) ◽  
pp. 239-259 ◽  
Author(s):  
Katherine J. Curtis White ◽  
Avery M. Guest
Keyword(s):  
Empirical Research ◽  
Social Ties ◽  
Frequency Of Contact ◽  
Relationship Of ◽  
The Relationship

Sociological theorists have generally emphasized the destructive effects of urbanization on social ties through the community lost perspective. A counterview, which we call the community transformed, has begun to emerge on the basis of other theorizing and empirical research. Yet the relationship of urbanization to social ties is still not well understood. In this article, we explore the total number of social ties, the number of kin and nonkin ties, the density or interconnection, and frequency of contact between ties among individuals residing within various U.S. settlement types. The results indicate that urbanization especially encourages the segmentation of social ties by discouraging density or interconnectedness. In addition, urbanization does have noteworthy effects in encouraging exclusively nonkin ties, which are presumably highly voluntaristic. Of the three definitions of urbanization that are tested, we find that metropolitanization is the most efficacious for understanding variations in social ties, especially exclusively nonkin ties.

The relationship of sexual abuse and HIV risk behaviors among heterosexual adult female STD patients

1997 ◽  
Vol 21 (2) ◽  
pp. 149-156 ◽  
Author(s):  
Nancy J. Thompson ◽  
Jennifer Sharpe Potter ◽  
Catherine A. Sanderson ◽  
Edward W. Maibach
Keyword(s):  
Sexual Abuse ◽  
Risk Behaviors ◽  
Adult Female ◽  
Hiv Risk ◽  
Hiv Risk Behaviors ◽  
Relationship Of ◽  
The Relationship

Altruism Among Female Macaca Radiata: Explanations and Analysis of Patterns of Grooming and Coalition Formation

Behaviour ◽  
1982 ◽  
Vol 79 (2-4) ◽  
pp. 162-188 ◽  
Author(s):  
Joan B. Silk
Keyword(s):  
Adult Female ◽  
Coalition Formation ◽  
Dominance Rank ◽  
Macaca Radiata ◽  
Bonnet Macaques ◽  
Lower Ranking ◽  
Relationship Of ◽  
The Relationship ◽  
Do So

AbstractAnalysis of the observed patterns of two forms of putative altruism (grooming and coalition formation) among adult female members of a group of captive bonnet macaques (Macaca radiata) indicates that both kinship and dominance rank influence the distribution and rate of these behaviors. Females groom their adult relatives more often and more reciprocally than they groom unrelated females of similar ranks. In addition, females are more likely to support their relatives than nonrelatives and are likely to incur greater risks when they do so. Grooming and coalition formation do not occur exclusively among kin. Females primarily groom higher ranking females and support unrelated females against females lower ranking than themselves. Although females do not preferentially support unrelated females that groom or support them most, they do refrain from harassing lower ranking females that are currently grooming them or a female higher ranking than themselves. Thus, by grooming a higher ranking female a female reduces the probability that she will be harassed by other females. The relationship of these results to predictions derived from several different sociobiological hypotheses is discussed.

FUNCTIONAL ZONATION OF ADRENOCORTICAL TISSUE IN THE BRUSH POSSUM (TRICHOSURUS VULPECULA)

1971 ◽  
Vol 49 (1) ◽  
pp. 131-NP ◽  
Author(s):  
G. P. VINSON ◽  
J. G. PHILLIPSt ◽  
I. CHESTER JONES ◽  
W. N. TSANG
Keyword(s):  
Adrenal Gland ◽  
Adult Female ◽  
Structure And Function ◽  
Trichosurus Vulpecula ◽  
And Function ◽  
Relationship Of ◽  
The Relationship ◽  
Special Zone

SUMMARY The relationship of structure and function in the adrenal gland of the possum Trichosurus vulpecula, has been studied using in-vitro incubation techniques. It was shown that both 17α-hydroxycorticosteroids and 17-deoxycorticosteroids were produced from radioactive pregnenolone and progesterone, and that these transformations occurred both in the definitive cortex as well as in a special zone of hypertrophied tissue found only in the adult female. In support of earlier findings, it was also shown that the adrenal cortex of the possum has a remarkable capacity to produce C19 steroids (including androstenedione and testosterone) from the radioactive precursors. While most of the transformations occurred with equal efficiency in both types of tissue, the reduction of androstenedione to testosterone seemed to take place more readily in the special hypertrophied zone of the adult female. In studies in vivo, it was found that levels of testosterone in the peripheral blood of the adult female possum were extremely high compared with man. Variations in testosterone levels were not apparently correlated with the stage of the oestrous cycle. The possible pathways by which the adrenal products are synthesized, and their physiological implications are discussed.

The relationship of the scleractinian corals to the rugose corals

Paleobiology ◽  
1980 ◽  
Vol 6 (02) ◽  
pp. 146-160 ◽  
Author(s):  
William A. Oliver
Keyword(s):  
Critical Points ◽  
Scleractinian Corals ◽  
Convincing Evidence ◽  
Early Triassic ◽  
Rugose Corals ◽  
History Of ◽  
The Subject ◽  
Relationship Of ◽  
The Relationship ◽  
Biologic Factors

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.

Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

1983 ◽  
Vol 41 ◽  
pp. 194-195
Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor
Keyword(s):  
High Resolution ◽  
Marine Invertebrates ◽  
Sea Urchins ◽  
Structural Features ◽  
Sea Stars ◽  
High Resolution Tem ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

Studies on Leukemogenic and Sarcomagenic Viruses

1970 ◽  
Vol 28 ◽  
pp. 156-157
Author(s):  
Leon Dmochowski
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Morphological Properties ◽  
Mode Of Development ◽  
Relationship Of ◽  
The Relationship

Electron microscopy has proved to be an invaluable discipline in studies on the relationship of viruses to the origin of leukemia, sarcoma, and other types of tumors in animals and man. The successful cell-free transmission of leukemia and sarcoma in mice, rats, hamsters, and cats, interpreted as due to a virus or viruses, was proved to be due to a virus on the basis of electron microscope studies. These studies demonstrated that all the types of neoplasia in animals of the species examined are produced by a virus of certain characteristic morphological properties similar, if not identical, in the mode of development in all types of neoplasia in animals, as shown in Fig. 1.

The relationship of IGE receptor topography to signaling activity in RBL-2H3 mast cells

1991 ◽  
Vol 49 ◽  
pp. 236-237
Author(s):  
J.R. Pfeiffer ◽  
J.C. Seagrave ◽  
C. Wofsy ◽  
J.M. Oliver
Keyword(s):  
Mast Cells ◽  
Protein A ◽  
Scattered Electron ◽  
Ige Receptor ◽  
Receptor Complexes ◽  
Ige Binding ◽  
Electron Imaging ◽  
Small Clusters ◽  
Relationship Of ◽  
The Relationship

In RBL-2H3 rat leukemic mast cells, crosslinking IgE-receptor complexes with anti-IgE antibody leads to degranulation. Receptor crosslinking also stimulates the redistribution of receptors on the cell surface, a process that can be observed by labeling the anti-IgE with 15 nm protein A-gold particles as described in Stump et al. (1989), followed by back-scattered electron imaging (BEI) in the scanning electron microscope. We report that anti-IgE binding stimulates the redistribution of IgE-receptor complexes at 37“C from a dispersed topography (singlets and doublets; S/D) to distributions dominated sequentially by short chains, small clusters and large aggregates of crosslinked receptors. These patterns can be observed (Figure 1), quantified (Figure 2) and analyzed statistically. Cells incubated with 1 μg/ml anti-IgE, a concentration that stimulates maximum net secretion, redistribute receptors as far as chains and small clusters during a 15 min incubation period. At 3 and 10 μg/ml anti-IgE, net secretion is reduced and the majority of receptors redistribute rapidly into clusters and large aggregates.

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