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Academic literature on the topic 'Modes of reproduction'

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Published: 10 December 2022
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Journal articles on the topic "Modes of reproduction"

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FISCHER, E. A. "Modes of Reproduction: Fish Reproduction." Science 227, no. 4693 (March 22, 1985): 1464–65. http://dx.doi.org/10.1126/science.227.4693.1464.

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Pichugin, Yuriy, Hye Jin Park, and Arne Traulsen. "Evolution of simple multicellular life cycles in dynamic environments." Journal of The Royal Society Interface 16, no. 154 (May 2019): 20190054. http://dx.doi.org/10.1098/rsif.2019.0054.

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The mode of reproduction is a critical characteristic of any species, as it has a strong effect on its evolution. As any other trait, the reproduction mode is subject to natural selection and may adapt to the environment. When the environment varies over time, different reproduction modes could be optimal at different times. The natural response to a dynamic environment seems to be bet hedging, where multiple reproductive strategies are stochastically executed. Here, we develop a framework for the evolution of simple multicellular life cycles in a dynamic environment. We use a matrix population model of undifferentiated multicellular groups undergoing fragmentation and ask which mode maximizes the population growth rate. Counterintuitively, we find that natural selection in dynamic environments generally tends to promote deterministic, not stochastic, reproduction modes.
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Liedtke, H. Christoph, Hendrik Müller, Julian Hafner, Johannes Penner, David J. Gower, Tomáš Mazuch, Mark-Oliver Rödel, and Simon P. Loader. "Terrestrial reproduction as an adaptation to steep terrain in African toads." Proceedings of the Royal Society B: Biological Sciences 284, no. 1851 (March 29, 2017): 20162598. http://dx.doi.org/10.1098/rspb.2016.2598.

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How evolutionary novelties evolve is a major question in evolutionary biology. It is widely accepted that changes in environmental conditions shift the position of selective optima, and advancements in phylogenetic comparative approaches allow the rigorous testing of such correlated transitions. A longstanding question in vertebrate biology has been the evolution of terrestrial life histories in amphibians and here, by investigating African bufonids, we test whether terrestrial modes of reproduction have evolved as adaptations to particular abiotic habitat parameters. We reconstruct and date the most complete species-level molecular phylogeny and estimate ancestral states for reproductive modes. By correlating continuous habitat measurements from remote sensing data and locality records with life-history transitions, we discover that terrestrial modes of reproduction, including viviparity evolved multiple times in this group, most often directly from fully aquatic modes. Terrestrial modes of reproduction are strongly correlated with steep terrain and low availability of accumulated water sources. Evolutionary transitions to terrestrial modes of reproduction occurred synchronously with or after transitions in habitat, and we, therefore, interpret terrestrial breeding as an adaptation to these abiotic conditions, rather than an exaptation that facilitated the colonization of montane habitats.
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Bunnell, F. L. "Reproduction of salal (Gaultheriashallon) under forest canopy." Canadian Journal of Forest Research 20, no. 1 (January 1, 1990): 91–100. http://dx.doi.org/10.1139/x90-013.

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Sexual and vegetative reproduction of salal (Gaultheriashallon Pursh) was measured under forest canopies of different closure. Sexual reproduction occurred only at ≤33% closure; vegetative reproduction occurred under sparse and dense closure. Crown closure influenced sexual reproduction primarily through interception of radiation and associated reductions in salal vigour. Irradiance had a greater influence on the mode of reproduction than did shoot density, and allocation of total reproductive effort (sexual plus vegetative) was contrary to optimality models, but consistent with resource limitation. No shoot <5 years old flowered; shared costs of flowering indicated physiological integration among salal shoots. Vegetative reproduction was negatively associated with age (r2 = 0.95), and 85% of the space occupied after 9 years of growth was occupied during the first 3 years. Under canopy the spatial pattern of salal shoots was better adapted to maintain plant persistence than to colonize new areas. Implications of salal's rates and modes of reproduction to forest and wildlife management are noted.
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Haccou, Patsy, and Maria Victoria Schneider. "Modes of Reproduction and the Accumulation of Deleterious Mutations With Multiplicative Fitness Effects." Genetics 166, no. 2 (February 1, 2004): 1093–104. http://dx.doi.org/10.1093/genetics/166.2.1093.

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Abstract Mutational load depends not only on the number and nature of mutations but also on the reproductive mode. Traditionally, only a few specific reproductive modes are considered in the search of explanations for the maintenance of sex. There are, however, many alternatives. Including these may give radically different conclusions. The theory on deterministic deleterious mutations states that in large populations segregation and recombination may lead to a lower load of deleterious mutations, provided that there are synergistic interactions. Empirical research suggests that effects of deleterious mutations are often multiplicative. Such situations have largely been ignored in the literature, since recombination and segregation have no effect on mutation load in the absence of epistasis. However, this is true only when clonal reproduction and sexual reproduction with equal male and female ploidy are considered. We consider several alternative reproductive modes that are all known to occur in insects: arrhenotoky, paternal genome elimination, apomictic thelytoky, and automictic thelytoky with different cytological mechanisms to restore diploidy. We give a method that is based on probability-generating functions, which provides analytical and numerical results on the distributions of deleterious mutations. Using this, we show that segregation and recombination do make a difference. Furthermore, we prove that a modified form of Haldane’s principle holds more generally for thelytokous reproduction. We discuss the implications of our results for evolutionary transitions between different reproductive modes in insects. Since the strength of Muller’s ratchet is reduced considerably for several forms of automictic thelytoky, many of our results are expected to be also valid for initially small populations.
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Prado, Cynthia, Masao Uetanabaro, and Célio Haddad. "Breeding activity patterns, reproductive modes, and habitat use by anurans (Amphibia) in a seasonal environment in the Pantanal, Brazil." Amphibia-Reptilia 26, no. 2 (2005): 211–21. http://dx.doi.org/10.1163/1568538054253375.

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AbstractAnnual patterns of breeding activity, reproductive modes, and habitat use are described for a frog community in a seasonal environment, in the southern Pantanal, Mato Grosso do Sul, Brazil. Data were collected monthly between January 1995 and December 1998. A total of 24 species from four families; Bufonidae (3 species), Hylidae (10 species), Leptodactylidae (9 species), and Microhylidae (2 species) were registered. Three reproductive activity patterns are recognized among these species: continuous, explosive, and prolonged; 50% of the species were explosive breeders. Seasonal pattern of reproduction was verified for three analyzed years (1995-1997); most species reproduced during the rainy season (Nov-Jan). The reproduction was aseasonal in 1998; unexpected rains in the dry season lead to an unusual breeding activity. Five reproductive modes were noted — 62.5% of the species have the generalized aquatic mode, and 33.3% deposit eggs embedded in foam nests. Many species used the same sites for reproduction, although temporal partitioning and calling site segregation was observed. The occurrence of many species that exhibit explosive breeding early in the rainy season is common in seasonal and open environments with variable and unpredictable rainfall, as is the case in the Pantanal.
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Frantz, Adrien, Manuel Plantegenest, and Jean-Christophe Simon. "Temporal habitat variability and the maintenance of sex in host populations of the pea aphid." Proceedings of the Royal Society B: Biological Sciences 273, no. 1603 (August 15, 2006): 2887–91. http://dx.doi.org/10.1098/rspb.2006.3665.

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The evolutionary maintenance of sex, despite competition from asexual reproduction, has long intrigued the evolutionary biologists owing to its numerous apparent short-term costs. In aphids, winter climate is expected to determine the maintenance of sexual lineages in the high latitude zones owing to their exclusive ability to produce frost-resistant eggs. However, diverse reproductive modes may coexist at a local scale where climatic influence is counteracted by microgeographical factors. In this study, we tested the influence of local habitat characteristics on regional coexistence of reproductive modes in the pea aphid, Acyrthosiphon pisum . In the laboratory, the induction of sexual morph production of many pea aphid genotypes from the local fields of annual (pea and faba bean) and perennial (alfalfa and red clover) crops in Western France indicated that A. pisum lineages from annual crops had a significantly higher investment in sexual reproduction than A. pisum lineages from the perennial hosts. We propose that temporal habitat variability exerts a selective pressure to maintain the sexual reproduction in A. pisum . The ecological and evolutionary consequences of the association between the mode of reproduction and the host population on gene flow restriction and on ecological specialization are discussed.
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Bourdieu, Pierre. "Stratégies de reproduction et modes de domination." Actes de la recherche en sciences sociales 105, no. 5 (December 1, 1994): 3–12. http://dx.doi.org/10.3917/arss.p1994.105n1.0003.

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Ghasarian, Christian. "L'anthropologie face aux nouveaux modes de reproduction." Journal des anthropologues 60, no. 1 (1995): 87–94. http://dx.doi.org/10.3406/jda.1995.1901.

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Bourdieu, Pierre. "Stratégies de reproduction et modes de domination." Actes de la recherche en sciences sociales 105, no. 1 (1994): 3–12. http://dx.doi.org/10.3406/arss.1994.3118.

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Dissertations / Theses on the topic "Modes of reproduction"

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Schneider, Maria Victoria. "Modes de reproduction chez le parasitoi͏̈de solitaire Venturia canesces." Lyon 1, 2003. http://www.theses.fr/2003LYO10071.

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Venturia canescens, un parasitoi͏̈de ichneumonidé de chenilles de piralidés, a deux modes de reproduction : arrhénotoque, (mâles haploi͏̈des et femelles diploi͏̈des)) et thélytoque (des femelles vierges engendrent des filles diploi͏̈des). Cette thélytoquie n'est pas l'effet de bactéries symbiotiques. Dans le Sud de la France, les deux modes de reproduction coexistent en sympatrie. La thèse traite des questions soulevées par cette coexistence. Une étude de la distribution géographique et une analyse moléculaire des populations, ont montré l'existence d'un clone thélytoque très répandu. Cependant quelques individus thélytoques sont génétiquement très proches des individus arrhénotoques. Une importante partie de la variabilité chez les thélytoques est due à un flux génique à partir de mâles arrhénotoques. Pour mieux comprendre la coexistence des deux modes de reproduction, différents traits d'histoire de vie et compromis génétiques reflétants des différentes pressions de sélection ont été étudiés.
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Eyer, Pierre-André. "Modes de reproduction et diversité génétique chez les fourmis du genre Cataglyphis." Doctoral thesis, Universite Libre de Bruxelles, 2014. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209190.

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Les insectes sociaux représentent le paradigme de la vie coopérative dans le règne animal. Ceci repose sur l’existence d’une division des activités reproductrices entre des individus reproducteurs (les reines et les mâles) et une majorité d’ouvrières sacrifiant leurs propres potentialités reproductives pour assurer l’essentiel des tâches logistiques nécessaires à l’essor des sociétés. Chez les Hyménoptères sociaux, l’analyse comparative des stratégies de reproduction révèle que la structure monogyne (une reine par société) et monandre (un seul accouplement par reine) est l’état ancestral des sociétés. Cette structure favorise une corrélation génétique élevée entre les ouvrières et le couvain qu’elles élèvent et, par conséquent, leur succès reproductif global (inclusive fitness). Cependant, un nombre croissant d’études génétiques montre que la structure des sociétés peut fortement s’éloigner de ce pattern. Ceci est particulièrement manifeste chez les fourmis, lesquelles présentent un très large polymorphisme social se traduisant par une grande variabilité du nombre de femelles reproductrices au sein des sociétés. Les formicidés sont également remarquables par la diversité de leurs modes de reproduction. Cette diversité concerne la fréquence des accouplements (monandrie/polyandrie) ou encore l’exploitation conditionnelle des modes de reproductions sexuée et asexuée. Chez quelques espèces, les futures reines sont en effet produites par parthénogenèse (elles sont des quasi-clones de leur mère), alors que les ouvrières sont issues d'une reproduction sexuée classique. Cette stratégie exceptionnelle permet aux reines d'accroître le taux de transmission de copies de leurs gènes dans la descendance, tout en conservant les bénéfices d'une diversité génétique dans la force ouvrière. Cette grande diversité de structures sociales et de modes de reproduction suggère l’action de nombreuses pressions sélectives. Les travaux réalisés dans le cadre de cette thèse de doctorat visent à déterminer les facteurs responsables du large polymorphisme social et des nombreux modes de reproduction observés chez les fourmis désertiques du genre Cataglyphis. Ils sont articulés autour de deux axes principaux.

Les analyses phylogénétiques montrent que la polyandrie est ancestrale au sein du genre Cataglyphis. Le premier axe de ce travail a pour but d’étudier les causes évolutives justifiant le maintien d’un tel système de reproduction au sein de ce genre. Ce travail porte sur les avantages d’une diversité génétique accrue parmi les ouvrières. Une telle diversité génétique permettrait notamment d'accroître le polymorphisme de taille des ouvrières et l'efficacité de la division du travail [Chapitre 1], ou la résistance aux pathogènes de la force ouvrière [Chapitre 2]. [1] Ce premier travail a été réalisé sur Cataglyphis cursor, une espèce strictement monogyne et polyandre. Les résultats de cette étude révèlent une très grande fidélité des ouvrières à la tâche. Ils montrent l’existence d’une association significative entre la tâche réalisée par une ouvrière et sa lignée paternelle, ainsi qu’entre la taille des ouvrières et la tâche effectuée. [2] Le second travail de cette thèse a été réalisé chez C. mauritanica. Nos résultats montrent que la résistance aux pathogènes diffère entre ouvrières issues de différentes lignées paternelles lorsque ces dernières sont isolées. Curieusement, cette différence s’estompe lorsque les lignées paternelles sont regroupées au sein des sociétés polyandres. Dès lors, la polyandrie permettrait d’homogénéiser l’immunité des sociétés. Nos données montrent cependant que la résistance des ouvrières à Metarhizium anisopliae n’est pas corrélée à la diversité génétique de la colonie ou au nombre d’accouplements des reines.

Le second axe de ce travail porte sur les stratégies de reproduction remarquables observées chez les espèces de Cataglyphis appartenant au groupe altisquamis :C. velox, C. mauritanica, C. humeya et C. hispanica. Ces espèces partagent une stratégie unique dans le règne animal, appelée hybridogénèse sociale. L’hybridogénèse classique est un système reproductif dans lequel les parents issus de lignées génétiques distinctes s’hybrident. Alors que les génomes maternels et paternels sont exprimés dans la lignée somatique des descendants, le génome paternel est systématiquement écarté de la lignée germinale. En conséquence, seul le génome maternel est transmis aux générations futures. Dans le schéma d’hybridogénèse sociale reporté dans ces travaux, les reines s’accouplent systématiquement avec un mâle originaire d’une lignée génétique distincte. Elles utilisent la reproduction sexuée pour la production d’une caste ouvrière stérile intégralement hybride (analogue à la lignée somatique) et la reproduction asexuée par parthénogénèse pour la production des castes reproductrices mâles et femelles (analogues à la lignée germinale). Dans ce système, bien que les génomes paternels et maternels soient exprimés dans la caste ouvrière, seul le génome maternel est transmis aux descendants reproducteurs [Chapitre 3]. Le groupe altisquamis est représenté par plusieurs espèces au sein desquelles deux lignées génétiques s’hybrident systématiquement pour la production de la caste ouvrière. Le dernier chapitre de cette thèse [4] est une analyse phylogéographique des espèces de ce groupe dans la péninsule ibérique. Les résultats confirment l’existence d’une seule paire de lignées génétiques au sein de chaque espèce. Ces résultats révèlent également une contradiction entre les marqueurs nucléaires et mitochondriaux traduisant la complexité du système reproductif. Ces travaux soulignent l’ambiguïté des relations phylogéniques entre espèces d’un tel système et discutent de son implication dans la spéciation des espèces hybridogénétiques.

Social insects represent the most extreme form of cooperative life in the animal kingdom. This is based on the existence of a division of reproductive activities between the reproductive individuals (queens and males) and a majority of workers performing all logistical tasks at the expense of their own reproduction. In social Hymenoptera, comparative analysis of reproductive strategies reveals that colonies headed by a single mated queen (monogyny/monoandry) is the ancestral structure of colonies. This structure provides a high genetic correlation between the workers and the brood they raise and, therefore, their overall reproductive success (inclusive fitness). However, an increasing number of genetic studies reveal that the reproductive structure of colonies can strongly differ from this pattern. This is particularly obvious in ants, which have a very large social polymorphism resulting in a large variability in the number of reproductive females within colonies. The Formicidae are also remarkable for the diversity of their modes of reproduction. This diversity relates to mating frequency (monoandry/polyandry) or conditional use of sexual and asexual reproduction. In some species, new queens are produced by parthenogenesis (they are almost clones of their mothers), while the workers arise from a classical sexual reproduction. By using alternative modes of reproduction for queen and worker castes, queens can increase the transmission rate of their genes to their reproductive female offspring while maintaining genetic diversity in the worker population. This high diversity of social structures and modes of reproduction suggests the occurrence of many selective forces. This thesis aimed at determining environmental and genetic factors responsible for the large social polymorphism and the high diversity of reproductive modes display by Cataglyphis desert ants. This thesis is divided into two main parts.

Phylogenetic analyses show that polyandry is ancestral across the genus Cataglyphis. The first part of this thesis examines the genetic hypothesis to account for the evolution and maintenance of multiple mating by queen in this genus. This work focuses on the benefits of increased genetic diversity among workers. Such genetic diversity may increase the size polymorphism of the worker force and improve efficiency of the division of labor [Chapter 1] or increase pathogen resistance of the colony [Chapter 2]. In Chapter 1, the genetic hypothesis to enhance efficiency of division of labor was tested on Cataglyphis cursor, a strictly monogynous and polyandrous species. The results reveal a great fidelity in task performance by workers. They reveal a significant association between patriline and task preference: workers belonging to different patrilines differ in their propensity to perform a given task. We also found that worker size is closely associated with task specialization. The second work of this thesis [Chapter 2] was performed in C. mauritanica. Our results show that resistance to pathogens differs between workers from different patrilines when patrilines are raised separately. Surprisingly, this difference disappears when the patrilines are grouped within polyandrous colonies. Therefore, polyandry would standardize the overall resistance of colonies. Consistent with this result, our data show a positive association between the number of matings by the queens and colony resistance to Metarhizium anisopliae.

The second part of this thesis expounds the unorthodox reproductive strategies observed in species belonging to the group Cataglyphis altisquamis: C. velox, C. mauritanica, C. hispanica and C. humeya. These species share a unique strategy in the animal kingdom, called social hybridogenesis. Hybridogenesis is a sexual reproductive system, whereby parents from different genetic origin hybridize. Both the maternal and paternal genomes are expressed in somatic tissues, but the paternal genome is systematically excluded from the germ line, which is therefore purely maternal. Consequently, only the maternal genome spread across generations. Here, we report a unique case of hybridogenesis at a social level. Queens mate exclusively with males originating from a different genetic lineage than their own to produce hybrid workers, while they use parthenogenesis to produce the male and female reproductive castes. In consequences, all sterile workers (somatic line) are sexually produced hybridogens, whereas sexual forms (germ line) are clonally produced. Thus, only maternal genes are perpetuated across generations [Chapter 3]. The group C. altisquamis is represented by several hybridogenetic species in which two highly divergent genetic lineages co-occur, despite their constant hybridization. The last chapter of this thesis [Chapter 4] is a phylogeographic analysis of C. altisquamis species in the Iberian Peninsula. Our results confirm the existence of a single pair of genetic lineages within each species. Our results also reveal strong incongruences between nuclear and mitochondrial markers that reflect the reproductive system complexities. These studies reveal phylogenetic ambiguities among these hybridogenetic species and discuss the involvement of such unconventional system in speciation process.


Doctorat en Sciences
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Viviès, France-Line. "Modes de domination et mécanismes de reproduction le cas de la Martinique /." Lille 3 : ANRT, 1989. http://catalogue.bnf.fr/ark:/12148/cb37619171j.

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Odena, Sophie. "Les modes de garde de la petite enfance : facteurs de reproduction sociale et sexuée." Aix-Marseille 1, 2005. http://www.theses.fr/2005AIX10059.

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A partir d'une enquête qualitative qui étudie deux modes de garde externalisés (crèches collectives et assistantes maternelles), cette thèse analyse l'exercice quotidien des rôles parentaux et les modes d'intervention des professionnels de la petite enfance dans les pratiques éducatives des familles. La première partie montre que si le choix du mode de garde se prend "in fine" au sein du couple, il est conditionné en amont par les mesures que l'Etat met à la disposition des familles. La deuxième partie est consacrée à l'étude des interactions entre les familles et les modes de garde. Les caractéristiques sociales des parents et leur attitude tout au long du processus d'obtention conditionnant l'issue de leur demande. La dernière partie s'intéresse aux représentations des rôles parentaux véhiculées par les institutions et à la manière qu'elles ont d'interférer avec celles de la famille. Il s'agit de montrer dans quelle mesure ces institutions contribuent à la reproduction sociale et sexuée.
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Rodriguez, Lily. "Diversité et modes de reproduction du peuplement d'anoures de Cocha Cashu (parc national Manu, Pérou)." Paris 6, 1991. http://www.theses.fr/1991PA066312.

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Pour tester l'hypothèse avancée par Duellman, selon laquelle la richesse spécifique des anoures est supérieure en régimes de pluies non saisonniers, on a étudié le peuplement d'anoures de Cocha Cashu (12 sud, au Pérou). On a ensuite comparé ces résultats à ceux des études faites par Crump et Duellman à Santa Cécilia (0, en Equateur), site connu comme étant le plus riche en espèces d'anoures. Les comparaisons mettent en relief les variations dans les traits de reproduction, la richesse spécifique et l'abondance relative. Le peuplement de Cocha Cashu se compose de 81 espèces. Sa richesse spécifique et sa diversité en modes de reproduction, comparables à celles du peuplement de Santa Cécilia, ne renforcent pas l'hypothèse de Duellman. Les comparaisons allométriques des traits de reproduction, montrent que à Cocha Cashu, la taille des femelles, l'effort de reproduction et le diamètre des oeufs ont tendance à être plus grands qu'à Santa Cécilia. Les comparaisons entre la plaine d'inondation et la forêt sur terrasse, ne montrent pas de différences quant au nombre d'espèces par mode de reproduction, mais les abondances relatives d'individus par mode de reproduction diffèrent significativement entre les deux habitats. La comparaison avec Santa Cécilia montre une tendance similaire
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Jalalzadeh, Moghaddam Shahri Banafsheh. "Evolution intraspécifique du génome et modes de reproduction générateurs de diversité génétique chez Agaricus bisporus." Thesis, Bordeaux, 2014. http://www.theses.fr/2014BORD0420/document.

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Agaricus bisporus, le champignon de Paris, est un basidiomycète saprophytenaturellement présent dans la litière de cyprès (Cupressus macrocarpa). Il possède différentsmodes de reproduction. Pour étudier leur rôle dans la dynamique spatio-temporelle et l’évolutionde la diversité génétique au cours du temps, des dispositifs expérimentaux ont été mis en place.Dix souches sauvages d’Agaricus bisporus var. bisporus ont été sélectionnées, à partir de deuxpopulations françaises, sur leurs traits phénotypiques et génotypiques. L’étude de l’évolutionmoléculaire de leurs génomes a montré que, pour le génome mitochondrial, la mobilité desintrons de groupe I apparait comme la principale source de polymorphisme. Des taux desubstitution nucléotidique (nt) faibles ont été observés chez tous les types de séquencesmitochondriales (éléments mobiles, séquences géniques et inter géniques). Cette forteconservation, comparée avec les taux élevés de substitution nt des séquences nucléairessimilaires, contraste avec ce qui est généralement décrit dans l’évolution des séquencesfongiques. Des expériences de croisements entre sporocarpes et mycelia de souches sauvages ontété menées sur du compost, dans une chambre de culture, pour simuler l’implantation d’unepopulation naturelle. Pour les sporocarpes récoltés, les données montrent l’existence d’unphénomène parasexuel de Buller conduisant à des souches hybrides d’A. bisporus dans lachambre de culture et potentiellement dans la nature. Parallèlement, les mycelia de souchessauvages ont été introduits dans deux parcelles expérimentales de cyprès. L’analyse génotypiquedes sporocarpes récoltés la première année d’introduction n’a pas permis de mettre en évidencede souche hybride et les conditions climatiques de la seconde année n’ont pas permis d’obtenir defructification. Les dispositifs et outils mis au point doivent permettre un suivi génétique spatiotemporelde la population sur le long terme
Agaricus bisporus, the button mushroom, is a saprophytic basidiomycete naturallyfound in cypress litter (Cupressus macrocarpa). It possesses different modes of reproduction. Tostudy their role in the spatio-temporal dynamics and in the evolution of the genetic diversity,experimental systems have been set up. Ten wild strains of Agaricus bisporus var. bisporus havebeen selected, from two french populations, on both phenotypic and genotypic traits. Themolecular evolution of their genomes has shown that, for the mitochondrial genome, group Iintron mobility was the main source of gene polymorphism. Low nucleotide (nt) substitutionrates were found in all types of mitochondrial sequences (mobile elements, genic and intergenicones). This stringent conservation of mitochondrial sequences, when compared with the high ntsubstitution rates of their nuclear counterparts, contrasts to what is widely accepted in fungalsequence evolution. Mating experiments between sporocarps and mycelia of wild strains wereconducted on compost in a room culture, to simulate the implantation of a natural population.Among the collected sporocarps, results indicate the occurrence of a parasexual Bullerphenomenon leading to hybrid strains of A. bisporus in room culture and putatively in the wild.In parallel, mycelia of the wild strains have been introduced in two experimental plots of cypress.Genotypic analysis of the sporocarps collected from these plots in the first year of introduction,failed to evidence a hybrid strain. The climatic conditions of the second year did not allowobtaining fruiting-bodies. The developed experimental systems and tools must allow a followingat the genetic level of the spatio-temporal evolution of the population
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Loizillon, Guillaume. "Modes de description des sons et synthese sonore." Paris 8, 1996. http://www.theses.fr/1996PA081164.

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Le son est defini comme la conjonction d'un phenomene physique et d'une realite physiologique et psychologique. Pourtant, seule la perception auditive fonde le phenomene acoustique dans sa specificite sonore. La mise en parallele des grandeurs physiques avec les donnees du sens de l'ouie est une conception limitee. Les travaux avances en psycho-acoustique montrent que l'audition ne peut se resumer en l'etablissement de ce reseau. Il faut considerer les sons comme les composantes d'une scene auditive dont la musique est un modele particulier. Il devient alors necessaire d'analyser les specificites du son musical, en suivant les etapes historiques qui ont conduit a une definition de celui-ci, articulee sur les parametres de hauteur, de duree d'intensite et de timbre. Cette derniere composante apparait comme valeur centrale dans la musique contemporaine. Ce basculement d'une musique des hauteurs vers une musique du timbre, prend un caractere decisif avec l'apparition des techniques electriques du son. En un siecle, elles ont apporte au musicien une panoplie d'outils qui utilisent les virtualites du son transforme en electricite, puis en informations numeriques. Au sein de ces nouvelles ressources, la seconde partie du travail se consacre a la synthese sonore. Sont abordes les differents modes de synthese sonore a travers un ensemble d'exemples sonores realises avec deux categories de programmes: les modes de synthese de signal, ou l'on specifie les differentes parametres de l'onde acoustique. Les modes de synthese par modeles physiques ou l'on decrit l'interaction entre differents objets modelises : cordes, plaques, plectres, anches. . . Par-dela la mise en oeuvre de processus techniques, l'objectif de ce travail est de demontrer que l'activite de synthese sonore est un veritable enjeu pour la composition qu'il serait une erreur de penser comme un seul produit de la technologie
SOUND IS DEFINED AS THE JUNCTION BETWEEN A PHYSICAL PHENOMENON AND PHYSIOLOGICAL A PSYCHOLOGICAL REALITY. MEANWHILE, ONLY THE AUDITIVE PERCEPTION - ESTABLISHES ACOUSTIC PHENOMENON ITS SOUNDING SPECIFICITY. LINKING PHYSICAL DIMENSIONS WITH ELEMENTS OF HEARING IS A RESTRICTED IDEA. LEADING WORKS IN PSYCHOACOUSTIC SHOW THAT AUDITION CANNOT BE REDUCED TO THIS CONCEPT. SOUNDS HAVE TO BE CONSIDERED AS THE ELEMENTS OF AN AUDITION SCENE OF WHICH MUSIC IS A SPECIFIC CASE. THUS, IT IS NECESSARY TO ANALYSE SPECIFICITIES OF MUSICAL SOUND, FOLLOWING THE HISTORICAL WAY THAT LEAD TO A DEFINITION ARTICULATED AROUND PARAMETERS OF PITCH, DURATION, INTENSITY AND TIMBRE. THIS LAST DIMENSION APPEARS AS A CENTRAL VALUE IN CONTEMPORARY MUSIC. THIS TRANSITION FROM A MUSIC OF PITCH TO A MUSIC OF TIMBRE, TAKES A DECISIVE DIMENSION with THE BIRTH OF ELECTRICAL SOUND TECHNICS. IN THE TIME OF ONE CENTURY THOSE TECHNICS BROUGHT MUSICIANS A COLLECTION OF TOOLS THAT USES THE CAPACITIES OF SOUND TRANSFORMED IN ELECTRICITY THEN IN DIGITAL INFORMATION. AMONG THOSE RESSOURCES, THE SECOND PART OF THIS WORK TAKES SOUND SYNTHESIS AS SUBJECT. WE DISCUSS IN THIS PART OF DIFFERENT SYNTHESIS METHODS AND WE SHOW DIFFERENT PROGRAMMING EXAMPLES, SEPARATED IN TWO CATEGORIES. METHODS OF SIGNAL SYNTHESIS IN WHICH ALL THE PARAMETERS OF ACOUSTIC WAVES MUST BE SPECIFIED. PHYSICAL MODELING WHERE THE INTERACTION BETWEEN OBJECTS LIKE STRING, PLATE, TUBE, MASS, IS DESCRIBED BEYOND A TECHNICAL PROCESS, THE GOAL OF THIS WORK IS TO DEMONSTRATE THAT SOUND SYNTHESIS IS A GENUINE PART OF MUSICAL COMPOSITION TERRITORY. IT WOULD BE A MISTAKE TO REGARD ONLY AS A TECHNOLOGICAL PRODUCT
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Ancel, Caroline. "Le RFRP-3 et l’axe gonadotrope du hamster syrien : effets genre-dépendants et modes d’action." Thesis, Strasbourg, 2013. http://www.theses.fr/2013STRAJ042/document.

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Le peptide RFRP-3 joue un rôle dans la régulation de l’axe hypothalamo-hypophyso-gonadotrope des mammifères. Le but de cette étude était de déterminer l’implication du RFRP-3 dans la régulation de l’axe reproducteur du hamster Syrien. Nos résultats montrent que le RFRP-3 stimule l’axe gonadotrope chez le hamster Syrien mâle, tandis qu’il a des effets variables chez la femelle. En effet, chez la femelle le peptide inhibe l’axe reproducteur lorsqu’il est administré au moment du pic pré-ovulatoire de LH le jour du proestrus, et n’a pas d’effet pendant le diestrus. Nous avons poursuivi notre étude par la caractérisation des sites d’action du RFRP-3 chez le hamster Syrien, en démontrant que l’effet du peptide sur l’axe gonadotrope est médié directement ou indirectement par les neurones à GnRH. De plus, nous avons écarté l’hypothèse d’un effet hypophysiotrope du peptide chez cette espèce. Pour conclure, les résultats présentés soulèvent de nombreuses questions quant aux effets espèce- et genre-dépendants du RFRP-3 sur l’axe gonadotrope du mammifère
RFRP-3 has been shown to play a role in the regulation of the mammalian hypothalamic-pituitary-gonadal axis. The aim of this work was to determine the involvement of RFRP-3 in the regulation of the Syrian hamster reproductive axis. We report unprecedented results indicating that RFRP-3 stimulates the male Syrian hamster gonadotrophic axis, whereas it has variable effects in female Syrian hamsters. Indeed, in females the peptide inhibits the reproductive axis at the time of the LH surge on the day of proestrus, and has no effect during diestrus. We went on to characterize RFRP-3 sites of action in the Syrian hamster brain, and show that the effect of the peptide on the gonadotrophic axis is mediated directly or indirectly via GnRH neurons. Moreover, we clearly rule out the possibility of a hypophysiotrophic effect of RFRP-3 in this species. Taken together, the present data raise interesting questions regarding species- and sex-dependent effects of RFRP-3 on the mammalian gonadotrophic axis
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Souchon, Yves. "Reproduction du brochet (Esox lucius,L. 1758) et développement des brochetons en Dombes : éléments d'optimisation des modes de gestion extensive." Lyon 1, 1985. http://www.theses.fr/1985LYO10514.

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Souchon, Yves. "Reproduction du Brochet (Esox lucius, L. 1758) et développement des prochetons en Dombes éléments d'optimisation des modes de gestion extensive." Grenoble : ANRT, 1985. http://catalogue.bnf.fr/ark:/12148/cb37595184d.

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Books on the topic "Modes of reproduction"

1

Macfarlane, Alan. Marriage and love in England: Modes of reproduction 1300-1840. Oxford: Basil Blackwell, 1986.

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Marriage and love in England: Modes of reproduction, 1300-1840. Oxford, UK: B. Blackwell, 1986.

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Marriage and love in England 1300-1840: Modes of reproduction 1300-1840. Oxford: Basil Blackwell, 1987.

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Vuorela, Ulla. The women's question and the modes of human reproduction: An analysis of a Tanzanian village. Uppsala, Sweden: Scandinavian Institute of African Studies, 1987.

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Association internationale des démographes de langue française., ed. Les modes de régulation de la reproduction humaine: Incidences sur la fécondité : colloque international de Delphes, 6-10 octobre 1992. [Paris]: Presses universitaires de France, 1994.

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Constantinescu, Gheorghe, and Heide Schatten, eds. Animal Models and Human Reproduction. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2017. http://dx.doi.org/10.1002/9781118881286.

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Yulinov, Valeriy, Natal'ya Patrusheva, and Boris Kochurov. Demographics. ru: INFRA-M Academic Publishing LLC., 2021. http://dx.doi.org/10.12737/1020561.

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The textbook covers the main sections of the course "Demography": the object, subject and methods of demography, connection with other sciences; sources of data on the population; the main types and factors of population movement, modes of natural reproduction of the population; migration and reproduction of the population; demographic, ethnic and religious structure of the population; demographic policy of the state. Meets the requirements of the federal state educational standards of higher education of the latest generation. For students of higher educational institutions studying under the bachelor's degree programs 38.03.04 and master's degree programs 38.04.04 in the direction of "State and Municipal Management", as well as for all those interested in demographic problems and their solution.
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Mueller, Werner A., Monika Hassel, and Maura Grealy. Development and Reproduction in Humans and Animal Model Species. Berlin, Heidelberg: Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-662-43784-1.

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Carlson, John D. A model of the productivity of the northern pintail. Washington, D.C: U.S. Dept. of the Interior, Fish and Wildlife Service, 1993.

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Letty, Éric. Résistance au Meilleur des mondes: Essai. Paris: Pierre-Guillaume de Roux, 2015.

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Book chapters on the topic "Modes of reproduction"

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Lombardi, Julian. "Modes of Reproduction." In Comparative Vertebrate Reproduction, 43–60. Boston, MA: Springer US, 1998. http://dx.doi.org/10.1007/978-1-4615-4937-6_3.

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Andrews, Lori B. "Alternative Modes of Reproduction." In Reproductive Laws for the 1990s, 361–403. Totowa, NJ: Humana Press, 1989. http://dx.doi.org/10.1007/978-1-4612-3710-5_18.

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Subramanian, S., T. Boopathi, and D. Sagar. "Various Modes of Reproduction." In Reproductive Strategies in Insects, 1–16. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9781003043195-1.

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Lombardi, Julian. "Ovuliparity and Modes of Embryo Retention." In Comparative Vertebrate Reproduction, 253–81. Boston, MA: Springer US, 1998. http://dx.doi.org/10.1007/978-1-4615-4937-6_9.

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Priyadarshan, P. M. "Modes of Reproduction and Apomixis." In PLANT BREEDING: Classical to Modern, 77–89. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-7095-3_4.

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Brown, Jack, and Peter D. S. Caligari. "Modes of reproduction and types of cultivar." In An Introduction to Plant Breeding, 11–17. Oxford OX4 2DQ, UK: Blackwell Publishing Ltd, 2013. http://dx.doi.org/10.1002/9781118685228.ch2.

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Hamlett, William C., Antonio G. Ferri, and Maria A. Miglino. "Modes of Reproduction in the Elasmobranchs of Brazil." In Reproductive Biology of South American Vertebrates, 3–18. New York, NY: Springer New York, 1992. http://dx.doi.org/10.1007/978-1-4612-2866-0_1.

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Chavkin, Wendy, Barbara Katz Rothman, and Rayna Rapp. "Alternative Modes of Reproduction: Other Views and Questions." In Reproductive Laws for the 1990s, 405–9. Totowa, NJ: Humana Press, 1989. http://dx.doi.org/10.1007/978-1-4612-3710-5_19.

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Davis, Peggy C. "Alternative Modes of Reproduction: The Locus and Determinants of Choice." In Reproductive Laws for the 1990s, 421–31. Totowa, NJ: Humana Press, 1989. http://dx.doi.org/10.1007/978-1-4612-3710-5_21.

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MacDonald, Juliet. "Digits and Figures: A Manual Drawing Practice and its Modes of Reproduction." In The SAGE Handbook of Digital Dissertations and Theses, 315–33. 1 Oliver's Yard, 55 City Road London EC1Y 1SP: SAGE Publications, Inc., 2012. http://dx.doi.org/10.4135/9781446201039.n19.

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Conference papers on the topic "Modes of reproduction"

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Cortès, Sven, Christian Dettmann, Philipp Boche, Niclas Schneider, and Alexander Heubuch. "Impact of control types of a chassis dynamometer on the reproduction of real world driving scenarios." In FISITA World Congress 2021. FISITA, 2021. http://dx.doi.org/10.46720/f2021-epv-079.

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The introduction of the Worldwide Harmonized Light Vehicle Test Procedure (WLTP) and Real Driving Emissions (RDE) test requirements for the certification of passenger cars requires mobile emission measurements during real driving cycles in addition to the common emission tests on chassis dynamometer. Due to the randomness of traffic and environmental conditions, it is not possible to repeat a real driving cycle with the same results to investigate issues, for example, the application of engine and transmission control units. This represents a big challenge for the manufacturers research and development departments. It is necessary to know the relevant influences from the real operation of the vehicle in order to reproduce real driving cycles on a test bench. The selection of a adequate validation environment is based on defined target values with which the requirements for accuracy and reproducibility of the test bench can be evaluated. In the classic load simulation of real driving on a chassis dynamometer, the driving resistance coefficients are determined in coastdown tests and then adjusted on the chassis dynamometer. Subsequently, the mapping of the height profile is necessary for the consideration of the track topology. The determination of the elevation profile via barometric altitude pressure or GPS measurement technology respectively map material is very complex in the necessary accuracy. An alternative to this procedure is described by the control modes v-alpha, n-alpha, F-v and F-n. For example, the roll in v-alpha control mode is controlled to a defined vehicle speed, independent of the currently applied traction force. At the same time, the angle of the accelerator pedal alpha of the test object is adjusted to the same speed. Since both control systems follow time-based setpoint values and no driving resistance simulation is running in parallel, the v-alpha control mode does not depend on the knowledge of the driving resistance coefficients. The same applies to the above mentioned control modes. These control modes are particularly suitable for the improvement of data states in which the driving performance remains unaffected, for example for the application of emission behaviour. This paper deals on the necessary extensions for chassis dynamometers as a selected validation environment to be able to use these rule types and classifies them in the IPEK XiL framework. The necessary measured variables for the comparison of the control modes with each other and with the classic load simulation are recorded in a specially constructed test vehicle both in real driving and in test bench operation mode. The results of speed, load and tractive force progression, as well as the energy flow within the vehicle, are then examined with regard to equality, accuracy and reproducibility.
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Menezes, Amor A., and Pierre T. Kabamba. "Resilient Self-Reproducing Systems." In ASME 2008 Dynamic Systems and Control Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/dscc2008-2284.

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This paper is motivated by the need to minimize the payload mass required to establish an extraterrestrial robotic colony. One approach for this minimization is to deploy a colony consisting of individual robots capable of self-reproducing. An important consideration once such a colony is established is its resiliency to large-scale environment or state variations. Previous approaches to learning and adaptation in self-reconfigurable robots have utilized reinforcement learning, cellular automata, and distributed control schemes to achieve robust handling of failure modes at the modular level. This work considers self-reconfigurability at the system level, where each constituent robot is endowed with a self-reproductive capacity. Rather than focus on individual dynamics, the hypothesis is that resiliency in a collective may be achieved if: 1) individual robots are free to explore all options in their decision space, including self-reproduction, and 2) they dwell preferentially on the most favorable options. Through simulations, we demonstrate that a colony operating in accordance with this hypothesis is able to adapt to changes in the external environment, respond rapidly to applied disturbances and disruptions to the internal system states, and operate in the presence of uncertainty.
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Bertini, Leonardo, Paolo Neri, Ciro Santus, and Alberto Guglielmo. "One Exciter per Sector Test Bench for Bladed Wheels Harmonic Response Analysis." In ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/gt2017-63628.

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Bladed wheel dynamic characterization is a crucial issue to avoid resonance excitations. The test bench presented in this paper was designed to independently excite the wheel sectors with one electromagnetic shaker each blade. Since a wide frequency range (1–10 kHz) is usually considered for bladed wheels, custom electromagnetic devices were designed, and then a closed-loop control software was also implemented. The global mode shapes of the wheel were then reconstructed through subsequent accelerometer measurements on all sectors to evaluate the harmonic response. The main target of the test rig is the reproduction of any operational condition by experimentally simulating an arbitrary number of stator vanes. In this way the response levels of the differently excited modes are measured and the modal damping is optimally quantified by providing a selective excitation of any number of nodal diameters. Preliminary results showed how the test setup actually allows to excite those modes with a specific number of nodal diameters, however, also exposed some difficulties to avoid small load components with different numbers of nodal diameters.
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Bredmose, Henrik, Peter Slabiak, Lasse Sahlberg-Nielsen, and Flemming Schlütter. "Dynamic Excitation of Monopiles by Steep and Breaking Waves: Experimental and Numerical Study." In ASME 2013 32nd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/omae2013-10948.

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An experiment with a flexible pile subjected to steep and breaking irregular waves has been conducted. The pile was constructed to represent a monopile wind turbine at scale 1:80. Two point masses were mounted on the pile to achieve the right scaled values for the first and second natural frequency. Emphasis is given to the observed impulsive excitation of the natural modes by steep and breaking waves. Additionally, springing and ringing-type continuous forcing of the first natural mode is seen for the moderately steep waves. The experiments were carried out at three depths and with two wave climates. The measured data for structural acceleration is analysed with respect to individual wave parameters. It is found that the largest accelerations occur for breaking waves. The measured wave field and structural response are reproduced numerically with a fully nonlinear potential flow solver for the undisturbed wave kinematics, combined with a finite element model with Morison-based forcing. A good overall reproduction of the wave field and structural response is achieved for two selected episodes. For some of the waves, however, the numerical response magnitude does not match the observed excitations. Ongoing work is therefore an investigation of breaking wave load models and their implementation into the present numerical frame work.
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Filippchenkova, Svetlana Igorevna, and Elena Alexandrovna Evstifeeva. "REPRODUCTIVE POTENTIAL OF RUSSIAN YOUTH: MANAGING HEALTH-RELATED QUALITY OF LIFE." In Themed collection of papers from Foreign International Scientific Conference «Trends in the development of science and Global challenges» by HNRI «National development» in cooperation with AFP. December 2021. Crossref, 2022. http://dx.doi.org/10.37539/man1.2021.27.40.012.

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The authors consider the problem of the reproductive potential of Russian students and health-related quality of life management in the context of individual psychological and subjective quality of students and behavioral risk factors in the field of reproduction. The results of a complex socio-psychological study of personality traits and demographic expectations of students of Tver universities are presented. Based on the obtained theoretical and empirical data, a medical and psychological model for managing risk factors and quality of life related to reproductive health has been developed and implemented.
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Owens, Patrick D., and A. Galip Ulsoy. "Self-Reproducing Machines: Preventing Degeneracy." In ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-14201.

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Machines produced by humans exhibit insufficient complexity to produce similar machines. As John von Neumann originally postulated, if biological systems are able to successfully reproduce, then there must be some characteristic that we can embed in machines to give them the ability to reproduce. Such a self-reproductive machine, also imbued with the ability to do constructive work, could prove enormously useful to the human race. This paper considers a simple self-reproducing machine, which consists of a 2-DOF, planar robot arm capable of picking up and placing the components of another arm. If the robot places the components within the allowable tolerance, then the original arm has successfully reproduced. An assembly line is constructed, so that a self-reproduction process can proceed along a track. If this process eventually fails because one robot is not capable of assembling another, then the system is said to be degenerate. Otherwise, the system is sustainable. A kinematic model that maps component placement errors from one generation of the robot arm to the next was derived. The system exhibited exponential growth in component placement errors. Thus, this self-reproduction system is degenerate. This system is then augmented to provide error-correction during the assembly process. With the application of error-correction the self-reproduction process is made sustainable. The minimal amount of error-correction required to achieve sustainable self-reproduction was investigated through sensor quantization, and it was shown that the amount of fidelity in the error-correction signal determines the success of the self-reproduction process. This self-reproduction system was also analyzed in the context of Kabamba's Generation Theory, which could predict the results obtained through simulation regarding degeneracy or sustainability.
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Mikova, Rositza. "TRENDS AND PECULIARITIES IN THE DEVELOPMENT OF THE BIRTH RATE IN THE RURAL AREAS OF SOUTH CENTRAL BULGARIA." In AGRIBUSINESS AND RURAL AREAS - ECONOMY, INNOVATION AND GROWTH 2021. University publishing house "Science and Economics", University of Economics - Varna, 2021. http://dx.doi.org/10.36997/ara2021.231.

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Regarding the negative trends in the birth rate, South Central Bulgaria is no exception. The decrease in the birth rate in this part of the country, especially in the period 2011-2020, is a result of the economic crisis and its impact on the living standards of the population. In recent years, the value orientations of the population have changed a lot. Women of all ethnic and religious groups in the region demonstrate a new type of reproductive behavior. The age structure has deteriorated and the fertile contingents have significantly decreased. Each municipality has already adopted the model of simple reproduction of the population. In South Central Bulgaria, favorable conditions for stable demographic development no longer exist.
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"Reproductive Behaviour: Methodological Issues of Research and Accounting in Demographic Policy." In XII Ural Demographic Forum “Paradigms and models of demographic development”. Institute of Economics of the Ural Branch of the Russian Academy of Sciences, 2021. http://dx.doi.org/10.17059/udf-2021-2-1.

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The article examines some aspects of the determination of reproductive behaviour, whose research results open up great opportunities for their ambiguous interpretation. New methodological approaches are necessary in order to improve the correctness of such studies. This applies to the analysis of the relationship between the age at birth of the first child and planned number of children, the effect of living standards on reproductive behaviour, self-assessment of obstacles associated with the birth of children. Particular attention is paid to a barely explored issue of the impact of value systems on reproductive intentions in the context of combined motives for the birth of children and self-assessment of relevant obstacles. Value systems play a significant role in determining reproductive behaviour, which should be taken into account in demographic policy.
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Koniuszewski, Karol, and Pawel D. Domanski. "Reproduction of equipment wear characteristics with kernel regression." In 2016 21st International Conference on Methods and Models in Automation and Robotics (MMAR). IEEE, 2016. http://dx.doi.org/10.1109/mmar.2016.7575259.

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"Assessment of the Dynamics of the Main Indicators of Population Reproduction in the Republic of Khakassia in the Context of Siberian and All-Russian Trends in the Post-Soviet Period." In XII Ural Demographic Forum “Paradigms and models of demographic development”. Institute of Economics of the Ural Branch of the Russian Academy of Sciences, 2021. http://dx.doi.org/10.17059/udf-2021-2-17.

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The article presents the dynamics of population reproduction processes in the Republic of Khakassia, comparing the data of the last census conducted in the USSR in 1989 and similar indicators of the Siberian Federal District and Russia as a whole. It is shown that after the rapid deterioration of both components of population reproduction in the 1990s, the demographic situation in the country has been significantly improving since 2006, including due to targeted demographic policy measures. However, in the last years, negative trends in demographic processes have formed, primarily because of a decrease in the number of births. As a result, after 10 years of positive natural growth in the Republic of Khakassia (2007–2016), the population decline resumed with a negative trend that continues to the present. The age structure, which has changed dramatically in comparison with the Soviet period, will determine further negative prospects in the demographic sphere. The research results can be used to improve demographic policy, including at the regional level.
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Reports on the topic "Modes of reproduction"

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Zhang, Peter. Reproduction of 'Simulating Relief Payments: An Interactive Model'. Social Science Reproduction Platform, July 2021. http://dx.doi.org/10.48152/ssrp-nhsd-z066.

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Lott, Casey A., Steven F. Railsback, Colin J. Sheppard, and Michael C. Koohafkan. Developing and Testing TernCOLONY 1.0: An Individual-based Model of Least Tern Reproduction. Fort Belvoir, VA: Defense Technical Information Center, June 2013. http://dx.doi.org/10.21236/ada587603.

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Werren, John H., Einat Zchori-Fein, and Moshe Coll. Parthenogenesis-Inducing Microorganisms in Parasitic Hymenoptera: Their Mode of Action and Utilization for Improvement of Biological Control Agents. United States Department of Agriculture, June 1996. http://dx.doi.org/10.32747/1996.7573080.bard.

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Wolbachia are intracellular bacteria known to cause reproductive and sex ratio disorders in many insects. In various parasitic Hymenoptera, Wolbachia induce thelytokous reproduction. The overall goal of this research was the improvement of biological control agents by reversion of their mode of reproduction. This was attempted from two directions: 1) studying the effect of naturally occurring Wolbachia on the thelytokous species Muscidifuraxuniraptor and 2) trying to transmit thelytoky-inducing Wolbachia to Nasoniavitripennis. In M. uniraptor, gamete duplication was found to be the mode of diploidy restoration and Wolbachia density had a strong effect on sex ratio but not on host fitness. Studies on the natural horizontal transmission of Wolbachia between Nasonia wasps and their Protocalliphora hosts using the Wolbachia Outer Surface Protein (WOSP) gene revealed that (a) two Nasonia species (N. giraulti and N. longicornis) possess closely related strains of B-group Wolbachia, but N. vitripennisapparently acquired B Wolbachia by horizontal transmission from an unknown source, (b) Nasonia and its Protocalliphora host have similar Wolbachia, and (c) the Protocalliphora Wolbachia WOSP gene is a recombinant between the one found in N. giraulti/longicornis and N. vitripennis. Results show parasitoid-host insect transmission of Wolbachia and recombination among Wolbachia strains. Results from gynandromorph studies suggest a novel mechanism of sex determination in Nasonia.
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Heifetz, Yael, and Michael Bender. Success and failure in insect fertilization and reproduction - the role of the female accessory glands. United States Department of Agriculture, December 2006. http://dx.doi.org/10.32747/2006.7695586.bard.

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The research problem. Understanding of insect reproduction has been critical to the design of insect pest control strategies including disruptions of mate-finding, courtship and sperm transfer by male insects. It is well known that males transfer proteins to females during mating that profoundly affect female reproductive physiology, but little is known about the molecular basis of female mating response and no attempts have yet been made to interfere with female post-mating responses that directly bear on the efficacy of fertilization. The female reproductive tract provides a crucial environment for the events of fertilization yet thus far those events and the role of the female tract in influencing them are poorly understood. For this project, we have chosen to focus on the lower reproductive tract because it is the site of two processes critical to reproduction: sperm management (storage, maintenance, and release from storage) and fertilization. E,fforts during this project period centered on the elucidation of mating responses in the female lower reproductive tract The central goals of this project were: 1. To identify mating-responsive genes in the female lower reproductive tract using DNA microarray technology. 2. In parallel, to identify mating-responsive genes in these tissues using proteomic assays (2D gels and LC-MS/MS techniques). 3. To integrate proteomic and genomic analyses of reproductive tract gene expression to identify significant genes for functional analysis. Our main achievements were: 1. Identification of mating-responsive genes in the female lower reproductive tract. We identified 539 mating-responsive genes using genomic and proteomic approaches. This analysis revealed a shift from gene silencing to gene activation soon after mating and a peak in differential gene expression at 6 hours post-mating. In addition, comparison of the two datasets revealed an expression pattern consistent with the model that important reproductive proteins are pre-programmed for synthesis prior to mating. This work was published in Mack et al. (2006). Validation experiments using real-time PCR techniques suggest that microarray assays provide a conservativestimate of the true transcriptional activity in reproductive tissues. 2.lntegration of proteomics and genomics data sets. We compared the expression profiles from DNA microarray data with the proteins identified in our proteomic experiments. Although comparing the two data sets poses analyical challenges, it provides a more complete view of gene expression as well as insights into how specific genes may be regulated. This work was published in Mack et al. (2006). 3. Development of primary reproductive tract cell cultures. We developed primary cell cultures of dispersed reproductive tract cell types and determined conditions for organ culture of the entire reproductive tract. This work will allow us to rapidly screen mating-responsive genes for a variety of reproductive-tract specifi c functions. Scientific and agricultural significance. Together, these studies have defined the genetic response to mating in a part of the female reproductive tract that is critical for successful fertllization and have identified alarge set of mating-responsive genes. This work is the first to combine both genomic and proteomic approaches in determining female mating response in these tissues and has provided important insights into insect reproductive behavior.
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Hadgu, Teklu, Gordon John Appel, Alexey E. Malashev, and Clay Payne. Reproduction of the Yucca Mountain Project TSPA-LA Model Runs using TSPA Computing Systems. Office of Scientific and Technical Information (OSTI), September 2015. http://dx.doi.org/10.2172/1458806.

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Hadgu, Teklu, Gordon John Appel, Alexey E. Malashev, and Clay Payne. Reproduction of the Yucca Mountain Project TSPA-LA Model Runs using TSPA Computing Systems. Office of Scientific and Technical Information (OSTI), September 2015. http://dx.doi.org/10.2172/1458847.

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Ohad, Nir, and Robert Fischer. Control of Fertilization-Independent Development by the FIE1 Gene. United States Department of Agriculture, August 2000. http://dx.doi.org/10.32747/2000.7575290.bard.

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A fundamental problem in biology is to understand how fertilization initiates reproductive development. During plant reproduction, one sperm cell fuses with the egg to form an embryo, whereas a second sperm cell fuses with the adjacent central cell nucleus to form the endosperm tissue that supports embryo and/or seedling development. To understand the mechanisms that initiate reproduction, we have isolated mutants of Arabidopsis that allow for replication of the central cell and subsequent endosperm development without fertilization. In this project we have cloned the MEA gene and showed that it encode a SET- domain polycomb protein. Such proteins are known to form chromatin-protein complexes that repress homeotic gene transcription and influence cell proliferation from Drosophylla to mammals. We propose a model whereby MEA and an additional polycomb protein we have cloned, FIE , function to suppress a critical aspect of early plant reproduction and endosperm development, until fertilization occurs. Using a molecular approach we were able to determine that FIE and MEA interact physically, suggesting that these proteins have been conserved also during the evolution of flowering plants. The analysis of MEA expression pattern revealed that it is an imprinted gene that displays parent-of- origin-dependent monoallelic expression specifically in the endosperm tissue. Silencing of the paternal MEA allele in the endosperm and the phenotype of mutant mea seeds support the parental conflict theory for the evolution of imprinting in plants and mammals. These results contribute new information on the initiation of endosperm development and provide a unique entry point to study asexual reproduction and apomixis which is expected to improve crop production.
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Opriessnig, T., and Patrick G. Halbur. Lack of reproduction of the hallmark porcine circovirus type 2-associated lesions in a mouse model. Ames (Iowa): Iowa State University, January 2005. http://dx.doi.org/10.31274/ans_air-180814-1092.

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Hadgu, Teklu, and Gordon John Appel. Reproduction of the Yucca Mountain Project TSPA-LA Uncertainty and Sensitivity Analyses and Preliminary Upgrade of Models. Office of Scientific and Technical Information (OSTI), September 2016. http://dx.doi.org/10.2172/1431496.

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Liambila, Wilson, Francis Obare, Chi-Chi Undie, Harriet Birungi, Shiphrah Kuria, Ruth Muia, and Assumpta Matekwa. Strengthening the delivery of comprehensive reproductive health services through the community midwifery model in Kenya. Population Council, 2012. http://dx.doi.org/10.31899/rh3.1028.

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