914 resultados para Within-sex competition


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Alliance formation is a critical dimension of social intelligence in political, social and biological systems. As some allies may provide greater ‘leverage’ than others during social conflict, the cognitive architecture that supports alliance formation in humans may be shaped by recent experience, for example in light of the outcomes of violent or non-violent forms intrasexual competition. Here we used experimental priming techniques to explore this issue. Consistent with our predictions, while men’s preference for dominant allies strengthened following losses (compared to victories) in violent intrasexual contests, women’s preferences for dominant allies weakened following losses (compared to victories) in violent intrasexual contests. Our findings suggest that while men may prefer dominant (i.e. masculine) allies following losses in violent confrontation in order to facilitate successful resource competition, women may ‘tend and befriend’ following this scenario and seek support from prosocial (i.e. feminine) allies and/or avoid the potential costs of dominant allies as long-term social partners. Moreover, they demonstrate facultative responses to signals related to dominance in allies, which may shape sex differences in sociality in light of recent experience and suggest that intrasexual selection has shaped social intelligence in humans.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

The purpose of this chapter is to analyse the way in which joint venture agreements can fall within the competition provisions of the Competition and Consumer Act 2010, and the circumstances in which authorisation may be available for joint venture collaborations.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

In May 2013 the President of the Office of Competition and Consumer Protection (UOKiK), the Polish Competition Authority, published its Annual Report for 2012. This piece provides an overview of the reported activities within the competition law & policy domain, and comments on some of them.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

There is increasing appreciation that hosts in natural populations are subject to infection by multiple parasite species. Yet the epidemiological and ecological processes determining the outcome of mixed infections are poorly understood. Here, we use two intracellular gut parasites (Microsporidia), one exotic and one co-evolved in the western honeybee (Apis mellifera), in an experiment in which either one or both parasites were administered either simultaneously or sequentially. We provide clear evidence of within-host competition; order of infection was an important determinant of the competitive outcome between parasites, with the first parasite significantly inhibiting the growth of the second, regardless of species. However, the strength of this ‘priority effect’ was highly asymmetric, with the exotic Nosema ceranae exhibiting stronger inhibition of Nosema apis than vice versa. Our results reveal an unusual asymmetry in parasite competition that is dependent on order of infection. When incorporated into a mathematical model of disease prevalence, we find asymmetric competition to be an important predictor of the patterns of parasite prevalence found in nature. Our findings demonstrate the wider significance of complex multi-host–multi-parasite interactions as drivers of host–pathogen community structure

Relevância:

90.00% 90.00%

Publicador:

Resumo:

Every year around 100 million male piglets are castrated in the EU, usually without anaesthesia or post-operative analgesia. This surgical intervention is painful and stressful. Several main players within the pig industry have voluntarily agreed to end the practice of surgical pig castration in the EU by 2018. One alternative to castration is entire male pig production. However, entire males behave differently than castrates, for example, by performing more mounting behaviour, which is suggested to be a welfare problem. The aim of our study was to develop a comprehensive ethogram of different types of mounting and to investigate properties, causes and consequences of mounting behaviour in finishing pigs. The study included 80 entire male and 80 female pigs from two farrowing batches born six weeks apart. Mixed sex and single-sex housing of pigs are both common in pig farming, so to ensure our study was representative, the 160 pigs were assigned to social groups of 20 in three treatments: entire male pigs only (MM, 2 groups, n = 40), entire females only (FF, 2 groups, n = 40) and entire males and females mixed together (MF, 4 groups, n = 80). Measurements took place during the final six weeks before slaughter (between 63.5 and 105.5 kg). Observations of mounting behaviour on 12 days per batch suggested that: (i) males mounted more than females, (ii) within sex, there was no effect of treatment on the amount of mounting (although the statistical power of the study to detect these effects was low), and (iii) there were individual differences in mounting that were stable over time (within sex). Classification of mounting into different categories revealed that sexual mounting was most common overall and in males but only rare in females. Compared to other types of mounting (e.g. caused by crowding or during a fight), sexual mounts lasted longer and provoked more screaming by the recipient. There were no relationships between mounting behaviour on the one hand and dominance rank in food competition tests, the circulating levels of sex hormones (oestradiol, testosterone and progesterone) at the end of the study, the health scores (lameness and scratches) or weight gain on the other hand. The stable individual differences of mounting over time suggest that mounting behaviour is a trait of the individual rather than the appearance of random outbreaks. However, these differences in mounting cannot be explained by dominance behaviour or by differences in sex hormone concentrations that could indicate the onset of puberty. Mounting behaviour and in particular sexual mounting provoked high pitched screaming of the recipients indicating that mounting is a welfare problem. For the welfare assessment of entire male pig production the performance of mounting behaviour should be considered. (C) 2013 Elsevier B.V. All rights reserved.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

After generally discussing models in ecology and economics that combine competition, optimization, and evolution, this article concentrates on models of intraspecific competition. It demonstrates the importance of diversity/inequalities within populations of species and other environments for the sustainability of their populations, given the occurrence of environmental change. This is demonstrated both for scramble (open-access) and contest competition. Implications are drawn for human populations and industrial organization. The possibility is raised that within-industry competition may not always exist between firms in all stages of the development of a new industry. Policy implications are considered. For example, it is argued that policies designed to encourage intense business competition and maximum economic efficiency have the drawback of eventually making industries highly vulnerable to exogenous economic changes.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Reform of Australia’s inconsistent Commonwealth, State and Territory consumer laws is now a reality. The 1 January 2011 commencement of the Australian Consumer Law (ACL), within the Competition and Consumer Act 2010, is the culmination of a long process of consultation. Unifying and rationalising the plethora of laws, this new Act sees the disappearance of the “Trade Practices Act” and the amendment of a raft of State and Territory legislation; the new national regime informed by them operates in their stead. This is indisputably the most comprehensive change in the history of the Trade Practices Act 1974. This book aims to assist practitioners, academics and students understand the Australian Consumer Law regime and its impact. It summarises the history and constitutional basis of the ACL, explaining how the ACL will be implemented, amended and enforced. In addition it explores how the various general and specific protections interrelate, and the scope of their overlap, and considers the content of the ACL, and the principal changes from the provisions of the Trade Practices Act.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

A single-generation dataset consisting of 1,730 records from a selection program for high growth rate in giant freshwater prawn (GFP, Macrobrachium rosenbergii) was used to derive prediction equations for meat weight and meat yield. Models were based on body traits [body weight, total length and abdominal width (AW)] and carcass measurements (tail weight and exoskeleton-off weight). Lengths and width were adjusted for the systematic effects of selection line, male morphotypes and female reproductive status, and for the covariables of age at slaughter within sex and body weight. Body and meat weights adjusted for the same effects (except body weight) were used to calculate meat yield (expressed as percentage of tail weight/body weight and exoskeleton-off weight/body weight). The edible meat weight and yield in this GFP population ranged from 12 to 15 g and 37 to 45 %, respectively. The simple (Pearson) correlation coefficients between body traits (body weight, total length and AW) and meat weight were moderate to very high and positive (0.75–0.94), but the correlations between body traits and meat yield were negative (−0.47 to −0.74). There were strong linear positive relationships between measurements of body traits and meat weight, whereas relationships of body traits with meat yield were moderate and negative. Step-wise multiple regression analysis showed that the best model to predict meat weight included all body traits, with a coefficient of determination (R 2) of 0.99 and a correlation between observed and predicted values of meat weight of 0.99. The corresponding figures for meat yield were 0.91 and 0.95, respectively. Body weight or length was the best predictor of meat weight, explaining 91–94 % of observed variance when it was fitted alone in the model. By contrast, tail width explained a lower proportion (69–82 %) of total variance in the single trait models. It is concluded that in practical breeding programs, improvement of meat weight can be easily made through indirect selection for body trait combinations. The improvement of meat yield, albeit being more difficult, is possible by genetic means, with 91 % of the variation in the trait explained by the body and carcass traits examined in this study.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Competition is an immensely important area of study in economic theory, business and strategy. It is known to be vital in meeting consumers’ growing expectations, stimulating increase in the size of the market, pushing innovation, reducing cost and consequently generating better value for end users, among other things. Having said that, it is important to recognize that supply chains, as we know it, has changed the way companies deal with each other both in confrontational or conciliatory terms. As such, with the rise of global markets and outsourcing destinations, increased technological development in transportation, communication and telecommunications has meant that geographical barriers of distance with regards to competition are a thing of the past in an increasingly flat world. Even though the dominant articulation of competition within management and business literature rests mostly within economic competition theory, this thesis draws attention to the implicit shift in the recognition of other forms of competition in today’s business environment, especially those involving supply chain structures. Thus, there is popular agreement within a broad business arena that competition between companies is set to take place along their supply chains. Hence, management’s attention has been focused on how supply chains could become more aggressive making each firm in its supply chain more efficient. However, there is much disagreement on the mechanism through which such competition pitching supply chain against supply chain will take place. The purpose of this thesis therefore, is to develop and conceptualize the notion of supply chain vs. supply chain competition, within the discipline of supply chain management. The thesis proposes that competition between supply chains may be carried forward via the use of competition theories that emphasize interaction and dimensionality, hence, encountering friction from a number of sources in their search for critical resources and services. The thesis demonstrates how supply chain vs. supply chain competition may be carried out theoretically, using generated data for illustration, and practically using logistics centers as a way to provide a link between theory and corresponding practice of this evolving competition mode. The thesis concludes that supply chain vs. supply chain competition, no matter the conceptualization taken, is complex, novel and can be very easily distorted and abused. It therefore calls for the joint development of regulatory measures by practitioners and policymakers alike, to guide this developing mode of competition.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The thesis provides an historical overview of the artist biopic that has emerged as a distinct sub-genre of the biopic as a whole, totalling some ninety films from Europe and America alone since the first talking artist biopic in 1934. Their making usually reflects a determination on the part of the director or star to see the artist as an alter-ego. Many of them were adaptations of successful literary works, which tempted financial backers by having a ready-made audience based on a pre-established reputation. The sub-genre’s development is explored via the grouping of films with associated themes and the use of case studies. These examples can then be used as models for exploring similar sets of data from other countries and time periods. The specific topics chosen for discussion include the representation of a single painter, for example, Vincent Van Gogh, to see how the treatment of an artist varies across several countries and over seventy years. British artist biopics are analysed as a case study in relation to the idea of them posing as a national stereotype. Topics within sex and gender studies are highlighted in analysis of the representation of the female artist and the queer artist as well as artists who have lived together as couples. A number of well-known gallery artists have become directors of artist biopics and their films are considered to see what particular insights a professional working artist can bring to the portrayal of artistic genius and creation. In the concluding part of the thesis it is argued that the artist biopic overall has survived the bad press which some individual productions have received and can even be said to have matured under the influence of directors producing a quality product for the art house, festival and avant-garde distribution circuits. As a genre it has proved extremely adaptable and has reflected the changing attitudes towards art and artists within the wider community. It has both encouraged renewed interest in the work of established national artists and also raised the profile of those relatively obscure such as Séraphine de Senlis and Pirosmani.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

El concepto de coopetencia surgen los planteamientos relacionados con los clústers y las redes empresariales, en donde empresas con características similares fortalecen sus relaciones para desarrollar mayores niveles de eficiencia o alcanzar objetivos que individualmente serian difíciles de lograr, especialmente en el caso de las pymes. Es fundamental que el estado desarrolle las relaciones y la conformación de iniciativas de asociatividad que permitan que la fluidez y los vínculos entre empresas, instituciones gubernamentales, financieras, universidades, centros de investigación, entre otros; para promover la integración de esfuerzos, la fluidez de información y el acceso a tecnologías, mejores posiciones competitivas. En Colombia desde hace aproximadamente 20 años, dentro de la política de competitividad del gobierno nacional (a partir del informe monitor), se ha identificado la importancia de las relaciones entre empresas e instituciones conexas para mejorar los estándares y la eficiencia que se pueda lograr para mantener una posición competitiva en los mercados internacionales.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Variations in demographic rates due to differential resource allocation between individuals are important considerations in the development of accurate population dynamic models. Systematic harvesting can alter age structure and/or reduce population density, conferring indirect positive benefits on the source population as a result of a consequent redistribution of resources between the remaining individuals. Independently of effects mediated through changes in density and competition, demographic rates can also be influenced by within-individual competition for resources. Harvesting dependent life stages can reduce an individual's current reproductive costs, allowing increased investment in its future fecundity and survival. Although such changes in demographic rates are well known, there has been little exploration of the potential impact on population dynamics. We use empirical data collected from a successfully reintroduced population of the Mauritius kestrel Falco punctatus to explore the population consequences of manipulating reproductive effort through harvesting. Consequent increases in an individual's future fecundity and survival allow source populations to withstand longer and more intensive harvesting regimes without being exposed to an increase in extinction risk, increasing maximum sustainable yields. These effects may also buffer populations against the impacts of stochastic events, but directional shifts in environmental conditions that increase reproductive costs may have detrimental population-level effects.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

An experiment was conducted to determine the effects of including cottonseed cake in rations for weaned growing pigs. Thirty-two Landrace x Large White pigs, weighing 20-24 kg, were included in four blocks formed on the basis of initial weight within sex in an otherwise completely randomized block design. The pigs were killed when they reached a live weight of 75.0 +/- 2.0 kg and the half careases were analysed into cuts and the weights of the organs were recorded. An estimate of the productivity of the pigs on each diet was calculated. Cottonseed cake reduced the voluntary feed intake (p < 0.001) and live weight gains (p < 0.001) and increased the heart, kidney and liver weights (p < 0.01). The pigs on the soya bean-based control diet took the shortest time to reach slaughter weight. The result was probably in part due to lysine deficiency and in part to the effect of free gossypol. It was found that it is at present cost-effective to include cottonseed cake in pig weaner grower diets up to 300 g/kg in Cameroon.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The authors illustrate how notions of poverty are constructed around specific ‘memes’, or replicating units of cultural information, around which concepts and ideas develop and change. Three ‘memes’ characterising definitions of poverty over the previous years were identified: ‘basic needs’, ‘multidimensional’ and ‘deprivation’. The analysis illustrated the semantic space in which each term was utilised and to the extent it changed and modified over time by different actors. The results revealed how ‘memes’ compete with one another across the discourse. Within this competition, older concepts are almost never fully abandoned, but rather repackaged and reutilised. Thus, new definitions of poverty are less innovative than portrayed in the wider literature.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Dados de rebanhos bovinos comerciais foram analisados com o objetivo de estimar as interações dos efeitos genéticos com o ambiente que podem influenciar a avaliação de características de crescimento em rebanhos de animais puros e cruzados. O conjunto de dados analisado foi obtido a partir de animais das raças Hereford, Nelore e seus cruzamentos. As características em estudo foram os pesos à desmama e ao sobreano dos animais. As análises estatísticas foram realizadas pelo método dos quadrados mínimos e o modelo proposto incluiu os efeitos de região, grupo de contemporâneos dentro de região, mês de nascimento e sexo do bezerro, os efeitos lineares e quadráticos para a idade do bezerro e idade da vaca ao parto, ambas analisadas dentro de sexo, e os efeitos de grupo genético e da interação grupo genético × região. de modo geral, o desempenho de todos os grupos genéticos foi influenciado pelo efeito de região. Além disso, observou-se tendência de que o aumento da proporção de genes zebuínos promoveu diminuição na diferença de desempenho entre as regiões. Todos os genótipos foram beneficiados no ambiente menos restritivo, o que indica a existência de interação genótipo-ambiente e comprova a importância de que sistemas de cruzamento sejam realizados de forma a manter a adaptação das matrizes e de seus produtos.