Nuptial gift chemistry reveals convergent evolution correlated with antagonism in mating systems of harvestmen (Arachnida, Opiliones)

Nuptial gifts are material donations given from male to female before or during copulation and are subject to sexual selection in a wide variety of taxa. The harvestman genus Leiobunum has emerged as a model system for understanding the evolution of reproductive morphology and behavior, as transitions between solicitous and antagonistic modes of courtship have occurred multiple times within the lineage and are correlated with convergence in genital morphology. We analyzed the free amino acid content of nuptial gift secretions from five species of Leiobunum using gas chromatography–mass spectrometry. Multivariate analysis of the free amino acid profiles revealed that, rather than clustering based on phylogenetic relationships, nuptial gift chemical composition was better predicted by genital morphology and behavior, suggesting that convergent evolution has acted on the chemical composition of the nuptial gift. In addition, we found that, species with solicitous courtship produce gifts consisting of a 19% larger proportion of essential amino acids as compared to those with more antagonistic courtship interactions. This work represents the first comparative study of nuptial gift chemistry within a phylogenetic framework in any animal group and as such contributes to our understanding of the evolution of reproductive diversity and the participant role of nuptial gift chemistry in mating system transitions

Phylogenetic exploration of mating system evolution in the eastern North American leiobunine harvestmen (Opiliones: Sclerosomatidae)

Understanding the basis for the vast diversity in reproductive structures found within the animal kingdom is a perennial issue in evolutionary biology. Meanwhile, taxonomists have long capitalized on the substantial genital diversity in the eastern North American leiobunine harvestmen for identifying and delimiting species, but no attempts have been made to explore the functional or evolutionary significance of this variety. Past discussion of the evolution of reproductive heterogeneity attributes genitalic diversification to female preferences, although recent work has also emphasized the (potentially competing) importance of intersexual conflict leading to sexually antagonistic coevolution. Here I test the overarching support for diversification of reproductive structures in leiobunine harvestmen via female choice and sexual conflict mechanisms of sexual selection. My dissertation work consisted of 1) reconstructing the phylogeny of eastern North American leiobunine harvestmen using molecular characters, 2) mapping and simulating relevant discrete morphological features, and 3), using biomechanical and kinetic reproductive data to test whether the direction of evolutionary change in reproductive characters within and between sexes is consistent with increasing sexual antagonism through evolutionary time via a comparative approach. I found support for the monophyly of the eastern North American leiobunine harvestmen, as well as evidence for an evolutionary transition from enticement-based mating to conflict-based systems. My novel uses of phylogenetic comparative methods to quantify mating systems demonstrate that leiobunine species form a continuum of reproductive diversity ranging from specialization in female enticement to precopulatory antagonistic contexts, with correlations between male and female discrete and continuous traits, suggesting long-term sexual coevolution has occurred. I conclude that mating system evolution has occurred in the leiobunine harvestmen, with sexual selection as its ultimate driver, and I offer hypotheses as to the origins of sexual conflict in these temperate lineages

Qualitative data for examining fixed and incremental concepts of language learning: A search for the stories behind students’ motivation

Although quantitative tools are often employed to examine students’ beliefs in language learning, qualitative interviews can offer further depth and insight on these beliefs, by shedding light on the detail of the experiences behind student perceptions. This is important to understanding student motivation in the language classroom, since beliefs form one of the important pillars behind motivation and language learning goals. The present study analyzed beliefs for 8 students in English for Hospitality vocational courses (2 male and 6 female from 25 to 43 years of age) in one-to-one, narrative interviews, looking both to the content of what students chose to share and the form in which they expressed themselves. This population is particularly interesting given that other studies in vocational studies indicate a lack of study persistence due to problems in motivation. Utilizing this qualitative, open-ended approach allowed the authors to more specifically examine how students conceive language learning when understood as a story of their experience with languages. The rich descriptions that emerge from this methodology have been imported for future curriculum planning, as they describe in more detail students’ tendencies to categorize language learning as something passive or active, as an object or as a process, which should be taken into account in course planning to optimize study persistence

Culture and motivation in English for hospitality students: Why integrative motivation may be essential

Hospitality students are the future negotiators of cultural interaction in our field, and how they imagine culture through their language studies is important. In particular, cultural concepts form an essential part of their motivation to learn a foreign language, in so far as it indicates their willingness to integrate into another culture, as Gardner (1960; 2007) and Dörnyei (2001;1994) have demonstrated. In fact, this integrative motivation has been recognized as one of the key elements for a successful learning outcome in languages. Our research explores whether integrative motivation is ubiquitous in the English for hospitality classroom. In a study with 51 adult English for Hospitality students, it found that students saw culture as malleable and showed a mixed motivational orientation. Based on these findings, some relevant curriculum implications are discussed. Apart from having the necessary practical skills required in the industry, hospitality students and workers also need to be effective communicators by understanding the roots of cultural awareness and the possibility of having more than one cultural identity

Comparative Language Learning Beliefs: Why Aptitude Matters

Language Learning Beliefs (LLB) are an important area for foreign and second language learning research that has grown considerably over the last decade, and which spans multi-disciplinary fields across education, linguistics and psychology (Martínez Agudo, 2014). These beliefs have become more important as they affect motivation and perhaps even language learning strategies (Zare-ee, 2010), though more research must be done in the latter area (Martínez Agudo, 2014). One understudied branch of LLB is that of language aptitude. Beliefs concerning language aptitude are not new, given that they appeared as a staple area of Horwitz’s seminal research for the BALLI questionnaire (Beliefs About Language Learning Inventory) (1987). However, beliefs on language aptitude need to be revisited given the multiple studies in social psychology on how beliefs affect learning when considering a given quality as innate or learned (Dweck, 2014). These studies show how believing intelligence to be fixed or incremental has a variety of consequences for learners that are fundamental for their long-term success in the classroom. Our aim in this paper is to merge these pertinent concepts to the foreign language classroom, in particular because the belief that intelligence is fixed or incremental mirrors the long-standing debate over language aptitude as innate or learned

Culture and motivation in English for hospitality students: why intwgrative motivation may be essential

Estudiantes de programas de hostelería y restauración deberán dominar la interacción cultural en su campo profesional, por lo que el concepto de negociación y entendimiento cultural debe estar estrechamente ligado al estudio de la lengua. En concreto, los conceptos culturales forman una parte esencial de la motivación para aprender idiomas extranjeros. La motivación integral aparece como uno de los elementos claves para el éxito en el aprendizaje de idiomas en distintos ámbitos y especialidades (Gardner (1960; 2007) y Dörnyei (2001; 1994). En este contexto, nuestra investigación explora si la motivación integral es ubicua en el aula de inglés para fines profesionales. En un estudio con 51 adultos cursando módulos de inglés profesional aplicado al sector hotelero, se observa que los alumnos entienden a la cultura como cambiable, y demuestran una motivación mixta hacia el aprendizaje lingüístico (integral e instrumental). A partir de las conclusiones extraídas, se presentan implicaciones curriculares para el desarrollo del inglés para fines ocupacionales en el aula. Más allá de tener las competencias lingüísticas necesarias, los estudiantes y futuros trabajadores de hostelería necesitan comunicarse de forma efectiva, entendiendo el concepto de multiculturalidad, y siendo conscientes de la importancia de la identidad cultural.Hospitality students are the future negotiators of cultural interaction in our field, and how they imagine culture through their language studies is important. In particular, cultural concepts form an essential part of their motivation to learn a foreign language, in so far as it indicates their willingness to integrate into another culture, as Gardner (1960; 2007) and Dörnyei (2001;1994) have demonstrated. In fact, this integrative motivation has been recognized as one of the key elements for a successful learning outcome in languages. Our research explores whether integrative motivation is ubiquitous in the English for hospitality classroom. In a study with 51 adult English for Hospitality students, it found that students saw culture as malleable and showed a mixed motivational orientation. Based on these findings, relevant curriculum implications are discussed. Apart from having the necessary practical skills required in the industry, hospitality students and workers also need to be effective communicators by understanding the roots of cultural awareness and the possibility of having more than one cultural identity.peerReviewe

Spatial Guilds in the Serengeti Food Web Revealed by a Bayesian Group Model

Food webs, networks of feeding relationships among organisms, provide fundamental insights into mechanisms that determine ecosystem stability and persistence. Despite long-standing interest in the compartmental structure of food webs, past network analyses of food webs have been constrained by a standard definition of compartments, or modules, that requires many links within compartments and few links between them. Empirical analyses have been further limited by low-resolution data for primary producers. In this paper, we present a Bayesian computational method for identifying group structure in food webs using a flexible definition of a group that can describe both functional roles and standard compartments. The Serengeti ecosystem provides an opportunity to examine structure in a newly compiled food web that includes species-level resolution among plants, allowing us to address whether groups in the food web correspond to tightly-connected compartments or functional groups, and whether network structure reflects spatial or trophic organization, or a combination of the two. We have compiled the major mammalian and plant components of the Serengeti food web from published literature, and we infer its group structure using our method. We find that network structure corresponds to spatially distinct plant groups coupled at higher trophic levels by groups of herbivores, which are in turn coupled by carnivore groups. Thus the group structure of the Serengeti web represents a mixture of trophic guild structure and spatial patterns, in contrast to the standard compartments typically identified in ecological networks. From data consisting only of nodes and links, the group structure that emerges supports recent ideas on spatial coupling and energy channels in ecosystems that have been proposed as important for persistence.Comment: 28 pages, 6 figures (+ 3 supporting), 2 tables (+ 4 supporting

DC-SIGN(+) Macrophages Control the Induction of Transplantation Tolerance

Tissue effector cells of the monocyte lineage can differentiate into different cell types with specific cell function depending on their environment. The phenotype, developmental requirements, and functional mechanisms of immune protective macrophages that mediate the induction of transplantation tolerance remain elusive. Here, we demonstrate that costimulatory blockade favored accumulation of DC-SIGN-expressing macrophages that inhibited CD8(+) T cell immunity and promoted CD4(+)Foxp3(+) Treg cell expansion in numbers. Mechanistically, that simultaneous DC-SIGN engagement by fucosylated ligands and TLR4 signaling was required for production of immunoregulatory IL-10 associated with prolonged allograft survival. Deletion of DC-SIGN-expressing macrophages in vivo, interfering with their CSF1-dependent development, or preventing the DC-SIGN signaling pathway abrogated tolerance. Together, the results provide new insights into the tolerogenic effects of costimulatory blockade and identify DC-SIGN(+) suppressive macrophages as crucial mediators of immunological tolerance with the concomitant therapeutic implications in the clinic.This work was supported by the COST Action BM1305: Action to Focus and Accelerate Cell Tolerogenic Therapies (A FACTT), the Mount Sinai Recanati/Miller Transplantation Institute developmental funds, AST/Pfizer Basic Science Faculty Development Grant, Ministerio de Educacióny Ciencia SAF2010-15062, SAF2013-48834-R, and Fundación Mutua Madrileñ a grants to J.O. A portion of this work appears as part of the doctoral thesis of P.C.S

Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis