scholarly journals On the Males and an Intersex-Like Specimen of the Parthenogenetic Saw-Fly Pristiphora Pallipes, LEP

1924 ◽  
Vol 1 (3) ◽  
pp. 391-412
Author(s):  
A. D. PEACOCK
Keyword(s):  
External Genitalia ◽  
Experimental Treatment ◽  
Egg Laying ◽  
Normal Male ◽  
Nurse Cells ◽  
Cent Solution ◽  
Chemical Solutions ◽  
Successive Generations ◽  
The Relationship ◽  
Small Ovary

1. Attempts have been made to modify the sex in various species of Tenthredinidæ by immersing leaves holding saw-fly eggs in chemical solutions during maturation which occurs during the first three hours after egg-laying. 2. In Pristiphorapallipes, Lep., which in England appears almost completely thelytokous, it is possible that sex-change has occurred as the result of such treatment for, in five experiments, eggs up to one and a half hours old treated for one hour in a 0.2 per cent, solution of magnesium sulphate (in distilled water) yielded 62 females, 2 males, and 1 intersexlike specimen. 3. Definitive interpretation of these appearances cannot be made until more experimental results are obtained, and more is known of the sex-ratio of the species. The breeding experiments of the writer and Miss E. F. Chawner, in England, involving the rearing of some 600 specimens during eight successive parthenogenetic generations show the male percentage to be between 0.5 per cent, and 1.75 per cent. In Canada Garlick finds it to be 2 per cent, fcom 232 individuals of five successive generations and part of the sixth; larvæ from cultivated bushes yielded 207 ♀ ♀ ; wild larvæ from a wild bush gave 4 per cent.--1 ♂ : 23 ♀ ♀. In South Europe Enslin states that the male is not rare. 4. The external characters of these rare English males and the abnormality, and the external genitalia of one male and the abnormality are described in detail. 5. Externally the abnormality shows the slim build of the male, but has certain female colour characters; its external genitalia comprise a male set, complete except for the genital plate, succeeded by a complete female set of which the two halves of the saw-sheath are smaller than normal, modified in shape and wide apart; the saws and saw-guides lie horizontally instead of sagittally; internally there is a spermatheca and paired gonads leading into normal male ducts ; each gonad to appearance resembles a small ovary with about five follicles, but cytologically they are almost empty except for a few indeterminate cells, a few nurse-cells, and relatively few spermatozoa. 6. This specimen may be either (a) a gynandromorph which genetically is a male with teratological gonads and possessing somatically certain substitutive female characters and arr additive female segment interpolated posteriorly; or (b) a gynandromorph genetically a male with teratological gonads and somatically a female with an additive male genitalring interpolated posteriorly; or (c) an intersex predominantly male (cf. moth intersexes of Goldschmidt, Harrison, and others). 7. Non-disjunction in either a male (X) or female (XX) pallipes egg during segmentation--and preferably during the later stages--could produce the condition of the abnormality. 8. The prime cause to non-disjunction in this almost completely thelytokous species cannot be abnormal intra- or inter-specific fertilisation, but may be hereditary or pathological--both unlikely--or physical or/and chemical disturbance in the relationship between the egg and its nidus in the leaf. Of the latter a possible natural cause is the occasional imperfect deposition of an egg so that a portion of it is exposed to the outer air, but the more likely explanation is the artificial experimental treatment. 9. The simultaneous appearance of two of the extremely rare English males and a unique abnormality from eggs treated as mentioned under (2) strengthen the possibility that these results were artificially produced. It is quite possible that the gonads of the abnormality were not intersexual but teratological, the chemical affecting the germ-tissue in shape only but not in sex. 10. Eight other sexual abnormalites in saw-flies, from other workers' records, are briefly described in their externals principally ; it is tentatively suggested that in the light of recent research they may be classified into two categories, (a) gynandromorphs, (b) intersexes; two of these specimens, Nematinus umbrinus, Zadd., taken wild, may be intersexes resultant upon an inter-specific cross umbrinus x ribesi

Certain aspects of the host-parasite relationship ofNematospiroides dubius(Baylis). II. The effect of sex on experimental infections in the rat (an abnormal host)

Parasitology ◽  
1961 ◽  
Vol 51 (3-4) ◽  
pp. 499-510 ◽  
Author(s):  
Colin Dobson
Keyword(s):  
Male Rats ◽  
Male Rat ◽  
Normal Male ◽  
Female Rat ◽  
Castrate Male ◽  
Parasite Relationship ◽  
Nematospiroides Dubius ◽  
Resistance To Infection ◽  
Host Parasite ◽  
The Relationship

1. The male rat is more susceptible to infections ofNematospiroides dubiusthan the female. As the rat grows older the resistance of the female rat to infection increases at a greater rate than that of the male.2. The course of the infection is modified by the sex of the host.3. More larvae penetrated the intestinal mucosa to encyst in the male than in the female. More larvae, however, formed cysts in the female than in the male rat by the fifth day.4. The male harboured more adult worms than the female rat, although this difference was not significant in the immature animals.5. The sex resistance of the rat toN. dubiusinfections was removed by bilateral gonadectomy. Castration decreased the susceptibility of the male rat, while spaying increased it in the female compared with the susceptibility in the respective normal hosts.6. Subsequent replacement of the homologous sex hormone in the gonadectomized rat restores the sex resistance, and may even increase it (particularly in the immature animals). Oestradiol increased the resistance of the spayed female rat, while testosterone increased the susceptibility of the castrate male rat to infection.7. Oestradiol implanted in castrate male rats increased the resistance of these hosts to a greater level than was shown in the normal male rat.8. The rat shows a marked age resistance over which the sex resistance is superimposed.9. The relationship between the sex of the host and its resistance to infection is discussed.This work was done during the tenure of a Department of Scientific and Industrial Research Studentship. My thanks are due to Dr E. T. B. Francis for his helpful and critical supervision and to Professor I. Chester Jones, in whose department the work was done, for the facilities he provided.

ASSESSMENT OF THE RELATIONSHIP BETWEEN THE INNOVATION LEVEL AND THE PROCESS OF DISTRIBUTING GENERATIONS OF AN INDUSTRIAL PRODUCT

2021 ◽  
Vol 7 (1) ◽  
pp. 146-162
Author(s):  
Albert E. Brand ◽  
Vladimir N. KUTRUNOV ◽  
Yuriy E. YAKUBOVSKIY
Keyword(s):  
Research Literature ◽  
Industrial Product ◽  
Next Generation ◽  
Rate Of Spread ◽  
Modeling And Forecasting ◽  
Game Console ◽  
Mathematical Formalization ◽  
Successive Generations ◽  
The Cost ◽  
The Relationship

This article assesses the relationship between the level of innovation and the process of spreading generations of an industrial product among the consumers on the example of generations of a stationary game console from Sony. This work follows the scientific direction of modeling and forecasting the spread of innovations; it contains the results of the analysis of the dynamics in the change of successive generations of an industrial product. The relevance of the research topic lies in the increased competition between companies engaged in innovative activities. This results in the need to determine the reasonable directions of technical, technological, and market development of the developed innovations in the form of new and improved products. This study uses the mathematical model by F. Bass, supplemented by the provisions of T. Islam and N. Meade on the variability of consumer behavior of different generations. The conducted review of research literature has revealed an insufficient elaboration of the issue of a qualitative and quantitative assessment of the relationship between the rate of spread of generations and the changes made to them. The authors draw hypotheses about the independence of the market potentials of successive generations from each other and the dependence of the level of innovativeness of the next generation of industrial products on technological, consumer and marketing changes. As a set of changes, this article proposes parameters of the purchase price and the cost of operating each generation. The authors have tested the hypothesis on statistical data of generational sales for 1994-2019 using correlation analysis. The results have shown the absence of the influence of the market potentials of successive generations from each other, as well as the presence of a connection and its strength between the level of innovativeness of the next generation and the changes made in the generations. The data obtained can be used for further mathematical formalization of the influence of the level of innovativeness of generations on the process of their distribution.

Coherence analysis of a family of weighted star-composed networks

2019 ◽  
Vol 33 (23) ◽  
pp. 1950264
Author(s):  
Meifeng Dai ◽  
Tingting Ju ◽  
Yongbo Hou ◽  
Jianwei Chang ◽  
Yu Sun ◽  
...  
Keyword(s):  
Kronecker Product ◽  
Future Research ◽  
Weight Factor ◽  
Node Number ◽  
Laplacian Eigenvalues ◽  
First Order ◽  
Successive Generations ◽  
Network Consistency ◽  
Relationship Of ◽  
The Relationship

Recently, the study of many kinds of weighted networks has received the attention of researchers in the scientific community. In this paper, first, a class of weighted star-composed networks with a weight factor is introduced. We focus on the network consistency in linear dynamical system for a class of weighted star-composed networks. The network consistency can be characterized as network coherence by using the sum of reciprocals of all nonzero Laplacian eigenvalues, which can be obtained by using the relationship of Laplacian eigenvalues at two successive generations. Remarkably, the Laplacian matrix of the class of weighted star-composed networks can be represented by the Kronecker product, then the properties of the Kronecker product can be used to obtain conveniently the corresponding characteristic roots. In the process of finding the sum of reciprocals of all nonzero Laplacian eigenvalues, the key step is to obtain the relationship of Laplacian eigenvalues at two successive generations. Finally, we obtain the main results of the first- and second-order network coherences. The obtained results show that if the weight factor is 1 then the obtained results in this paper coincide with the previous results on binary networks, otherwise the scalings of the first-order network coherence are related to the node number of attaching copy graph, the weight factor and generation number. Surprisingly, the scalings of the first-order network coherence are independent of the node number of initial graph. Consequently, it will open up new perspectives for future research.

Selective extraction of trace metals associated with hydrous aluminum oxides

1987 ◽  
Vol 65 (5) ◽  
pp. 984-989 ◽  
Author(s):  
Janece Slavek ◽  
William Frederick Pickering
Keyword(s):  
Metal Ions ◽  
Selective Extraction ◽  
Metal Species ◽  
Initial Surface ◽  
Aluminum Oxides ◽  
Hydrous Oxides ◽  
Soil Sediment ◽  
Trace Metal Content ◽  
Chemical Solutions ◽  
The Relationship

In soil/sediment analysis, subdivision of trace metal content into different categories is usually based on selective extraction schemes. To assess the disposition of metal ions bound to aluminum hydrous oxides in such schemes, suspensions of Al(OH)3gel, gibbsite, or alumina were loaded with up to 5 μ mol of Cu, Pb, Cd, or Zn ions prior to being extracted for 24 h with one of fifteen different chemical solutions. The percentage of sorbed ion retrieved varied along the reagent sequence: NaCl, CaCl2 < MgCl2, NH4NO3 < CH3COONH4, Na citrate, Na4P2O7 < EDTA, DTPA < CH3COOH, H2C2O4, HCl, HNO3. In each system, the recovery value varied with the initial surface loading (a function of sorption pH) and reflected changes in metal species form, e.g., bonded M2+, (MOH+), M(OH)2. With low loading levels up to 40% was displaced by salt solutions; with 1 to 2 μ mol sorbed, as little as 10% was displaced by acids or complex formers but this increased to ~90% with higher loadings. The relationship between sorption pH, amount sorbed, and extraction value was complex, and since in selective extraction schemes classification is based on recovery values, changes in initial retention parameters (e.g. system pH) lead to varying fractions of the different metal ions being classified as "ion exchangeable", "chemisorbed", and "incorporated in the lattice".

MORPHOLOGY OF THE FEMALE TERMINALIA IN LEPIDOPTERA, AND ITS TAXONOMIC SIGNIFICANCE

1972 ◽  
Vol 104 (7) ◽  
pp. 1055-1071 ◽  
Author(s):  
Akira Mutuura
Keyword(s):  
Morphological Characters ◽  
Egg Laying ◽  
Food Plants ◽  
Taxonomic Significance ◽  
Genealogical Tree ◽  
Genital Opening ◽  
Phylogenetic Classification ◽  
Relationship Of ◽  
The Relationship

AbstractIn the phylogenetic classification of the Lepidoptera, the position of the genital opening and its modifications help to clarify the relationship of the Zeugloptera to the lepidopterous suborders. Three different systems of the suborder classification of the Lepidoptera, into Homoneura and Heteroneura (Tillyard, Imms, etc.), Monotrysia and Ditrysia (Borner), and Dacnonypha, Monotrysia, and Ditrysia (Hinton), are not supported by evidence obtained in the study of the female genitalia.The development of the female terminalia is closely associated with the mode of oviposition. Several types of female terminalia are found in the primitive Lepidoptera (Hepialidae, Neopseustidae, Tischeriidae, Lyonetiidae, Agathiphagidae, Tineidae, Nepticulidae, and Eriocraniidae). They are divided into four categories: hepialid type — the eggs are dropped randomly; typical lepidopterous type — the eggs are laid on the surface of food plants; eriocraniid type — the eggs are laid inside the food plants; tineid type — the eggs are laid in crevices of food. Each of the types is derivable from the types occurring in Neopseustidae, Tischeriidae, Agathiphagidae, and Eriocraniidae, respectively. These types are still far removed from the type of female terminalia in Micropterygidae of the Zeugloptera.The modes of egg-laying as well as the morphological characters of the female genitalia must be taken into consideration in suborder classification of the Lepidoptera.A genealogical tree based on the female terminalia suggests four main branches: hepialid branch — includes Neopseustidae and Prototheoridae; typical lepidopterous branch — includes all Ditrysia and Nepticulidae; tineid branch — includes only Tineidae; eriocraniid branch — includes Incurvariidae, Prodoxidae, Adelidae, and Heliozelidae.

Analyse Experimentale Du Role De L'Ovitube Dans Le Comportement De Ponte De La Bruche Du Haricot (Acanthoscelides Obtectus Say- Coleoptera, Bruchidae)

Behaviour ◽  
1975 ◽  
Vol 54 (3-4) ◽  
pp. 258-277 ◽  
Author(s):  
Jean Pouzat
Keyword(s):  
Mechanical Stimulus ◽  
Egg Laying ◽  
Acanthoscelides Obtectus ◽  
The One ◽  
The Relationship ◽  
Acanthoscelides Obtectus Say ◽  
Egg Laying Behaviour ◽  
Made In ◽  
Important Stimulus

AbstractA resume is made of the major sequences of egg-laying behaviour, both in nature and on stored seeds, of the bean weevil. An experimental analysis of the role of the ovipositor in the act of egg-laying is then undertaken by simple techniques. It is observed that an important stimulus, with respect to this, is mechanical in nature: resulting from contact between the setae of the ovipositor on the one hand, and the seed and the "ground" on the other. Simply suspending the seed instead of leaving it lie on the cage bottom, suffices to reduce egg-laying and production significantly. Examination of egg-laying, when the substratum furnished is a trellis with suitable sized mesh, shows that an important aspect of the mechanical stimulus is in its concentrical character, i.e., the fact that it is applied to a greater number of setae all around the ovipositor. The result enables us to understand better the behaviour in nature, where there is a boring of the bean pod followed by egg-laying inside that pod through through the hole made. In the course of the paper some connected problems are evoked: - The relationship between egg-laying and production; - The more or less necessary character of the succession of the different sequences in egg-laying behaviour. Existence of intermediary cases, between individuals which can lay eggs only in the pod and those laying in the apparent absence of any stimulus, particularly stimuli connected with the bean; - Links between the phytophage and its host, remarks on the apparently unfavourable peculiarity of laying a great number of eggs in the same place, the possible consequences with respect to population dynamics.

scholarly journals Should 45,X/46,XY boys with no or mild anomaly of external genitalia be investigated and followed up?

2018 ◽  
Vol 179 (3) ◽  
pp. 181-190 ◽  
Author(s):  
Laurence Dumeige ◽  
Livie Chatelais ◽  
Claire Bouvattier ◽  
Marc De Kerdanet ◽  
Capucine Hyon ◽  
...  
Keyword(s):  
Cell Function ◽  
Pubertal Development ◽  
External Genitalia ◽  
Growth Spurt ◽  
Normal Male ◽  
Early Management ◽  
Abnormal Growth ◽  
Renal Malformations ◽  
Male Phenotype ◽  
End Of Puberty

Objective Few studies of patients with a 45,X/46,XY mosaicism have considered those with normal male phenotype. The purpose of this study was to evaluate the clinical outcome of 45,X/46,XY boys born with normal or minor abnormalities of external genitalia, notably in terms of growth and pubertal development. Methods Retrospective longitudinal study of 40 patients followed between 1982 and 2017 in France. Results Twenty patients had a prenatal diagnosis, whereas 20 patients had a postnatal diagnosis, mainly for short stature. Most patients had stunted growth, with abnormal growth spurt during puberty and a mean adult height of 158 ± 7.6 cm, i.e. −2.3 DS with correction for target height. Seventy percent of patients presented Turner-like syndrome features including cardiac (6/23 patients investigated) and renal malformations (3/19 patients investigated). Twenty-two patients had minor abnormalities of external genitalia. One patient developed a testicular embryonic carcinoma, suggesting evidence of partial gonadal dysgenesis. Moreover, puberty occurred spontaneously in 93% of patients but 71% (n = 5) of those evaluated at the end of puberty presented signs of declined Sertoli cell function (low inhibin B levels and increased FSH levels). Conclusion This study emphasizes the need to identify and follow-up 45,X/46,XY patients born with normal male phenotype until adulthood, as they present similar prognosis than those born with severe genital anomalies. Currently, most patients are diagnosed in adulthood with azoospermia, consistent with our observations of decreased testicular function at the end of puberty. Early management of these patients may lead to fertility preservation strategies.

Interactions between freshwater mussels and newts: a novel form of parasitism?

2008 ◽  
Vol 29 (4) ◽  
pp. 457-462 ◽  
Author(s):  
Edmée Engel ◽  
Klaus Groh ◽  
Richard Griffiths ◽  
Laura Wood ◽  
Laurent Schley
Keyword(s):  
Freshwater Mussels ◽  
Egg Laying ◽  
Interspecific Relationship ◽  
Triturus Cristatus ◽  
High Occurrence ◽  
Local Tissue ◽  
Lissotriton Helveticus ◽  
Bone Damage ◽  
Ecological Implications ◽  
The Relationship

Abstract Small freshwater mussels are sometimes found attached to the toes of aquatic phase amphibians, but the ecological implications of this interspecific relationship are unknown. Toe condition and mussel presence were recorded for newts caught in 37 ponds in Luxembourg between March and June 2007. All four local newt species were affected (Lissotriton helveticus, L. vulgaris, Mesotriton alpestris and Triturus cristatus), primarily by the mussel Sphaerium nucleus but also by Pisidium subtruncatum. Mussel attachment was observed in three ponds, with a particularly high occurrence in one pond, where 23% of newts were affected and significantly more toes were damaged than in other ponds. Mussels caused local tissue and bone damage to their host and may interfere with egg-laying. Twenty-two newts with attached mussels were observed in aquaria for up to 3 days: 13 mussels detached when the newt's toe fell off and nine remained attached. If the mussels benefit from the interaction through, for example, enhanced dispersal then the relationship between the two taxa represents a novel form of parasitism.

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