1,277 research outputs found
Gene flow and genetic structure in Nile perch, Lates niloticus, from African freshwater rivers and lakes
Background
Geological evolution of the African continent has been subject to complex processes including uplift, volcanism, desert formation and tectonic rifting. This complex geology has created substantial biogeographical barriers, and coupled with anthropogenic introductions of freshwater fishes, has influenced the genetic diversity, connectivity and sub-structuring of the teleost fauna. Nile perch, Lates niloticus, is an iconic fish in Africa and is of high commercial importance, both in the species' native range and where it has been translocated. However, the species is in decline and there is a need to understand its population genetic structure to facilitate sustainable management of the fishery and aquaculture development.
Methodology
Nile perch tissue samples were acquired from two West and four East (Lakes; Albert, Kyoga, Victoria and Turkana) African locations. Nineteen polymorphic microsatellite loci were used to study the genetic variation among populations across regions (West and East Africa), as well as between native and introduced environments within East Africa.
Principal findings and their significance
Results revealed strong and significant genetic structuring among populations across the sampled distribution (divergence across regions, FCT = 0.26, P = 0.000). STRUCTURE analysis at a broad scale revealed K = 2 clusters, the West African individuals were assigned to one cluster, while all individuals from the East African region, regardless of whether native or introduced, were assigned to another cluster. The distinct genetic clusters identified in the current study between the West and East African Nile perch, appear to have been maintained by presence of biogeographic barriers and restricted gene flow between the two regions. Therefore, any translocations of Nile perch should be carefully considered across the regions of West and East Africa. Further analysis at a regional scale revealed further structuring of up to K = 3 genetic clusters in East African Nile perch. Significantly (P < 0.05) lower genetic diversity based on analysis of allelic richness (AR) was obtained for the two translocated populations of Lake Kyoga (AR = 3.61) and Lake Victoria (AR = 3.52), compared to Nile perch populations from their putative origins of Lakes Albert (AR = 4.12) and Turkana (AR = 4.43). The lower genetic diversity in the translocated populations may be an indication of previous bottlenecks and may also indicate a difficulty for these populations to persist and adapt to climatic changes and anthropogenic pressures that are currently present in the East African region
SNP data reveals the complex and diverse evolutionary history of the blue-ringed octopus genus (Octopodidae: Hapalochlaena) in the Asia-Pacific
The blue-ringed octopus species complex (Hapalochlaena spp.), known to occur from Southern Australia to Japan, currently contains four formally described species (Hapalochlaena maculosa, Hapalochlaena fasciata, Hapalochlaena lunulata and Hapalochlaena nierstraszi). These species are distinguished based on morphological characters (iridescent blue rings and/or lines) along with reproductive strategies. However, the observation of greater morphological diversity than previously captured by the current taxonomic framework indicates that a revision is required. To examine species boundaries within the genus we used mitochondrial (12S rRNA, 16S rRNA, cytochrome c oxidase subunit 1 [COI], cytochrome c oxidase subunit 3 [COIII] and cytochrome b [Cytb]) and genome-wide SNP data (DaRT seq) from specimens collected across its geographic range including variations in depth from 3 m to >100 m. This investigation indicates substantially greater species diversity present within the genus Hapalochlaena than is currently described. We identified 10,346 SNPs across all locations, which when analysed support a minimum of 11 distinct clades. Bayesian phylogenetic analysis of the mitochondrial COI gene on a more limited sample set dates the diversification of the genus to ∼30 mya and corroborates eight of the lineages indicated by the SNP analyses. Furthermore, we demonstrate that the diagnostic lined patterning of H. fasciata found in North Pacific waters and NSW, Australia is polyphyletic and therefore likely the result of convergent evolution. Several “deep water” (>100 m) lineages were also identified in this study with genetic convergence likely to be driven by external selective pressures. Examination of morphological traits, currently being undertaken in a parallel morphological study, is required to describe additional species within the complex
Signatures of Adaptation and Acclimatization to Reef Flat and Slope Habitats in the Coral Pocillopora damicornis
Strong population-by-habitat interactions across environmental gradients arise from genetic adaptation or acclimatization and represents phenotypic variation required for populations to respond to changing environmental conditions. As such, patterns of adaptation and acclimatization of reef-building corals are integral to predictions of the future of coral reefs under climate warming. The common brooding coral, Pocillopora damicornis, exhibits extensive differences in host genetic and microbial symbiont community composition between depth habitats at Heron Island in the southern Great Barrier Reef, Australia. An 18-month reciprocal field transplant experiment was undertaken to examine the environmental and genetic drivers behind variation in survival, weight gain, heat tolerance and algal symbiont community between the reef flat and slope habitats. We observed population-by-habitat interactions for in situ partial mortality and weight gain, where trait-related fitness of natives was greater than transplants in most cases, consistent with local adaptation. On average, flat colonies transplanted to the slope had a relatively low partial mortality but minimal weight gain, whereas slope colonies transplanted to the flat had relatively high partial mortality and average weight gain. Experimental heat tolerance was always higher in colonies sourced from the flat, but increased when slope colonies were transplanted to the flat, providing evidence of acclimatization in these colonies. The performance of certain slope to flat transplants may have been driven by each colony’s algal symbiont (Symbiodiniaceae) community, and flat variants were observed in a small number of slope colonies that either had a fixed flat composition before transplantation or shuffled after transplantation. Host genotypes of previously identified genetic outlier loci could not predict survival following transplantation, possibly because of low sample size and/or polygenic basis to the traits examined. Local environmental conditions and Symbiodiniaceae composition may provide insight into the adaptive potential to changing environmental conditions
Unlocking Women's Leadership Potential: A Curricular Example for Developing Female Leaders in Academia
Women in academia face unique challenges when it comes to advancing to professorship. Using latest research about gender and academic leadership, we present a training curriculum that is sensitive to the unique demands of women in and aspiring to leadership positions in academia. The context-specific and evidence-based approach and a focus on self-directed leadership development are unique characteristics of the training. It aims to enhance women's motivation to lead, increase their knowledge about academic leadership, and empower them to seek the support they need to proactively work toward appointment to a professorship. We also delineate an evaluation framework, which addresses these targeted outcomes. The findings from a pilot program in Germany confirmed that the curriculum is effective in developing women as academic leaders. The discussion highlights the significance of a context-specific and evidence-based approach to women's leadership development in academia
Influence of firm size on the competencies required to management engineers in the Jordanian telecommunications sector
This is an Accepted Manuscript of an article published by Taylor & Francis in European Journal of Engineering Education on [13 jun 2016], available online:http://www.tandfonline.com/ doi/abs/10.1080/03043797.2016.1197890.[EN] The objective of this study is to identify the competencies required to
achieve success in the transition from higher education to the labour
market based on the perceptions of employers. This paper analyses the
assessments made by a group of engineering company employers. An
item-battery of 20 competencies was grouped into 3 dimensions by
using factor analysis. Subsequently, respondents scores were also
clustered into three groups and characterised through contingency
tables. The competencies demanded by employers were grouped into
business and finance, problem-solving and strategic planning. Significant
differences were found between responses from employers working in
medium and small companies, who placed more importance on
competencies related to problem-solving and strategic planning, and
employers in big companies, who were more concerned about the
difficulties of finding well-trained graduates. The findings from this
paper have important implications for research in the areas of higher
education and organisations that usually employ graduate engineers.The authors would like to thank the Education, Audiovisual and Culture Executive Agency (EACEA) [Tempus program. Project number 511074] of the European Commission for providing funding for conducting this study. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.Conchado Peiró, A.; Bas Cerdá, MDC.; Gharaibeh, KM.; Kaylani, H. (2016). Influence of firm size on the competencies required to management engineers in the Jordanian telecommunications sector. European Journal of Engineering Education. 1-14. doi:10.1080/03043797.2016.1197890S114ALLEN, J., & DE WEERT, E. (2007). What Do Educational Mismatches Tell Us About Skill Mismatches? A Cross-country Analysis. European Journal of Education, 42(1), 59-73. doi:10.1111/j.1465-3435.2007.00283.xBarrella, E. M., & Buffinton, K. W. (2009). Corporate Assessment of Strategic Issues in Technology Management. Engineering Management Journal, 21(1), 27-33. doi:10.1080/10429247.2009.11431795Bartram, D., Lindley, P. A., Marshall, L., & Foster, J. (1995). The recruitment and selection of young people by small businesses. Journal of Occupational and Organizational Psychology, 68(4), 339-358. doi:10.1111/j.2044-8325.1995.tb00592.xBehrends, T. (2007). Recruitment Practices in Small and Medium Size Enterprises. An Empirical Study among Knowledge-intensive Professional Service Firms. management revu, 18(1), 55-74. doi:10.5771/0935-9915-2007-1-55Boshuizen, H. P. A. (s. f.). Does Practice Make Perfect? Innovation and Change in Professional Education, 73-95. doi:10.1007/1-4020-2094-5_5Branine, M. (2008). Graduate recruitment and selection in the UK. Career Development International, 13(6), 497-513. doi:10.1108/13620430810901660Butler, C. J., & Chinowsky, P. S. (2006). Emotional Intelligence and Leadership Behavior in Construction Executives. Journal of Management in Engineering, 22(3), 119-125. doi:10.1061/(asce)0742-597x(2006)22:3(119)Carbone, T. A., & Gholston, S. (2004). Project Manager Skill Development: A Survey of Programs and Practitioners. Engineering Management Journal, 16(3), 10-16. doi:10.1080/10429247.2004.11415252Cassell, C., Nadin, S., Gray, M., & Clegg, C. (2002). Exploring human resource management practices in small and medium sized enterprises. Personnel Review, 31(6), 671-692. doi:10.1108/00483480210445962Cattell, R. B., & Vogelmann, S. (1977). A Comprehensive Trial Of The Scree And Kg Criteria For Determining The Number Of Factors. Multivariate Behavioral Research, 12(3), 289-325. doi:10.1207/s15327906mbr1203_2Chan, A. P. C., Ho, D. C. K., & Tam, C. M. (2001). Effect of Interorganizational Teamwork on Project Outcome. Journal of Management in Engineering, 17(1), 34-40. doi:10.1061/(asce)0742-597x(2001)17:1(34)Coll, R. K., & Zegwaard, K. E. (2006). Perceptions of desirable graduate competencies for science and technology new graduates. Research in Science & Technological Education, 24(1), 29-58. doi:10.1080/02635140500485340Cronbach, L. J. (1951). Coefficient alpha and the internal structure of tests. Psychometrika, 16(3), 297-334. doi:10.1007/bf02310555Dekker, R., de Grip, A., & Heijke, H. (2002). The effects of training and overeducation on career mobility in a segmented labour market. International Journal of Manpower, 23(2), 106-125. doi:10.1108/01437720210428379Elfenbein, D. W., Hamilton, B. H., & Zenger, T. R. (2010). The Small Firm Effect and the Entrepreneurial Spawning of Scientists and Engineers. Management Science, 56(4), 659-681. doi:10.1287/mnsc.1090.1130Farr, J. V., & Brazil, D. M. (2009). Leadership Skills Development for Engineers. Engineering Management Journal, 21(1), 3-8. doi:10.1080/10429247.2009.11431792Garen, J. E. (1985). Worker Heterogeneity, Job Screening, and Firm Size. Journal of Political Economy, 93(4), 715-739. doi:10.1086/261327Gharaibeh, K. M., Kaylani, H., Murphy, N., Brennan, C., Itradat, A., Al-Bataineh, M., … Bany Salameh, H. (2014). A Masters Programme in telecommunications management – demand-based curriculum design. European Journal of Engineering Education, 40(3), 267-284. doi:10.1080/03043797.2014.944104Hayes, J., Rose‐Quirie, A., & Allinson, C. W. (2000). Senior managers’ perceptions of the competencies they require for effective performance: implications for training and development. Personnel Review, 29(1), 92-105. doi:10.1108/00483480010295835Hersch, J. (1991). Education Match and Job Match. The Review of Economics and Statistics, 73(1), 140. doi:10.2307/2109696Hoegl, M., & Parboteeah, K. P. (2007). Creativity in innovative projects: How teamwork matters. Journal of Engineering and Technology Management, 24(1-2), 148-166. doi:10.1016/j.jengtecman.2007.01.008Hoegl, M., Praveen Parboteeah, K., & Gemuenden, H. G. (2003). When teamwork really matters: task innovativeness as a moderator of the teamwork–performance relationship in software development projects. Journal of Engineering and Technology Management, 20(4), 281-302. doi:10.1016/j.jengtecman.2003.08.001Van Hoorn, T. P. (1979). Strategic planning in small and medium-sized companies. Long Range Planning, 12(2), 84-91. doi:10.1016/0024-6301(79)90076-1HUSELID, M. A. (1995). THE IMPACT OF HUMAN RESOURCE MANAGEMENT PRACTICES ON TURNOVER, PRODUCTIVITY, AND CORPORATE FINANCIAL PERFORMANCE. Academy of Management Journal, 38(3), 635-672. doi:10.2307/256741Kaiser, H. F. (1958). The varimax criterion for analytic rotation in factor analysis. Psychometrika, 23(3), 187-200. doi:10.1007/bf02289233Kaufman, L., & Rousseeuw, P. J. (Eds.). (1990). Finding Groups in Data. Wiley Series in Probability and Statistics. doi:10.1002/9780470316801Krug, J. (1997). People Skills: Teamwork. Journal of Management in Engineering, 13(2), 15-16. doi:10.1061/(asce)0742-597x(1997)13:2(15)Male, S. A., Bush, M. B., & Chapman, E. S. (2010). Perceptions of Competency Deficiencies in Engineering Graduates. Australasian Journal of Engineering Education, 16(1), 55-68. doi:10.1080/22054952.2010.11464039Mao, X., Zhang, X., & AbouRizk, S. M. (2009). Enhancing Value Engineering Process by Incorporating Inventive Problem-Solving Techniques. Journal of Construction Engineering and Management, 135(5), 416-424. doi:10.1061/(asce)co.1943-7862.0000001Mendelsohn, R. (1998). Teamwork—The Key to Productivity. Journal of Management in Engineering, 14(1), 22-25. doi:10.1061/(asce)0742-597x(1998)14:1(22)Moore, B. V. (1921). Personnel selection of graduate engineers: The differentiation of apprentice engineers for training as salesmen, designers, and executives of production. Psychological Monographs, 30(5), i-85. doi:10.1037/h0093191Moy, J. W., & Lee, S. M. (2002). The career choice of business graduates: SMEs or MNCs? Career Development International, 7(6), 339-347. doi:10.1108/13620430210444367Nair, C. S., Patil, A., & Mertova, P. (2009). Re-engineering graduate skills – a case study. European Journal of Engineering Education, 34(2), 131-139. doi:10.1080/03043790902829281Passow, H. J. (2012). Which ABET Competencies Do Engineering Graduates Find Most Important in their Work? Journal of Engineering Education, 101(1), 95-118. doi:10.1002/j.2168-9830.2012.tb00043.xPinnington, A. H. (2011). Competence development and career advancement in professional service firms. Personnel Review, 40(4), 443-465. doi:10.1108/00483481111133336Reio, T. G., & Sutton, F. C. (2006). Employer assessment of work-related competencies and workplace adaptation. Human Resource Development Quarterly, 17(3), 305-324. doi:10.1002/hrdq.1176Robar, T. Y. (1998). Communication and Career Advancement. Journal of Management in Engineering, 14(2), 26-28. doi:10.1061/(asce)0742-597x(1998)14:2(26)Rowold, J., & Kauffeld, S. (2008). Effects of career‐related continuous learning on competencies. Personnel Review, 38(1), 90-101. doi:10.1108/00483480910920732Ruiz-Mercader, J., Meroño-Cerdan, A. L., & Sabater-Sánchez, R. (2006). Information technology and learning: Their relationship and impact on organisational performance in small businesses. International Journal of Information Management, 26(1), 16-29. doi:10.1016/j.ijinfomgt.2005.10.003Soliman, F., & Spooner, K. (2000). Strategies for implementing knowledge management: role of human resources management. Journal of Knowledge Management, 4(4), 337-345. doi:10.1108/13673270010379894Srour, I., Abdul-Malak, M.-A., Itani, M., Bakshan, A., & Sidani, Y. (2013). Career Planning and Progression for Engineering Management Graduates: An Exploratory Study. Engineering Management Journal, 25(3), 85-100. doi:10.1080/10429247.2013.11431985Sunindijo, R. Y., Hadikusumo, B. H., & Ogunlana, S. (2007). Emotional Intelligence and Leadership Styles in Construction Project Management. Journal of Management in Engineering, 23(4), 166-170. doi:10.1061/(asce)0742-597x(2007)23:4(166)Tanova, C. (2003). Firm size and recruitment: staffing practices in small and large organisations in north Cyprus. Career Development International, 8(2), 107-114. doi:10.1108/13620430310465534Teichler, U. (1999). Higher education policy and the world of work: changing conditions and challenges. Higher Education Policy, 12(4), 285-312. doi:10.1016/s0952-8733(99)00019-7Tsang, M. C., & Levin, H. M. (1985). The economics of overeducation. Economics of Education Review, 4(2), 93-104. doi:10.1016/0272-7757(85)90051-2Ward, J. H. (1963). Hierarchical Grouping to Optimize an Objective Function. Journal of the American Statistical Association, 58(301), 236-244. doi:10.1080/01621459.1963.10500845Zenger, T. R. (1994). Explaining Organizational Diseconomies of Scale in R&D: Agency Problems and the Allocation of Engineering Talent, Ideas, and Effort by Firm Size. Management Science, 40(6), 708-729. doi:10.1287/mnsc.40.6.708Zenger, T. R., & Lazzarini, S. G. (2004). Compensating for innovation: Do small firms offer high-powered incentives that lure talent and motivate effort? Managerial and Decision Economics, 25(67), 329-345. doi:10.1002/mde.119
Reducing Crowding by Weakening Inhibitory Lateral Interactions in the Periphery with Perceptual Learning
We investigated whether lateral masking in the near-periphery, due to inhibitory lateral interactions at an early level of central visual processing, could be weakened by perceptual learning and whether learning transferred to an untrained, higher-level lateral masking known as crowding. The trained task was contrast detection of a Gabor target presented in the near periphery (4°) in the presence of co-oriented and co-aligned high contrast Gabor flankers, which featured different target-to-flankers separations along the vertical axis that varied from 2λ to 8λ. We found both suppressive and facilitatory lateral interactions at target-to-flankers distances (2λ - 4λ and 8λ, respectively) that were larger than those found in the fovea. Training reduces suppression but does not increase facilitation. Most importantly, we found that learning reduces crowding and improves contrast sensitivity, but has no effect on visual acuity (VA). These results suggest a different pattern of connectivity in the periphery with respect to the fovea as well as a different modulation of this connectivity via perceptual learning that not only reduces low-level lateral masking but also reduces crowding. These results have important implications for the rehabilitation of low-vision patients who must use peripheral vision to perform tasks, such as reading and refined figure-ground segmentation, which normal sighted subjects perform in the fovea
From Crowds to Collaborators: Initiating Effort & Catalyzing Interactions Among Online Creative Workers
What lies between market and hierarchy? Insights from internalization theory and global value chain theory
In this paper, we suggest that internalization theory might be extended by incorporating complementary insights from GVC theory. More specifically, we argue that internalization theory can explain why lead firms might wish to externalize selected activities, but that it is largely silent on the mechanisms by which those lead firms might exercise control over the resultant externalized relationships with their GVC partners. We advance an explanation linking the choice of control mechanism to two factors: power asymmetries between the lead firms and their GVC partners, and the degree of codifiability of the information to be exchanged in the relationship
Fine-Scale Genetic Structure Arises during Range Expansion of an Invasive Gecko
Processes of range expansion are increasingly important in light of current concerns about invasive species and range shifts due to climate change. Theoretical studies suggest that genetic structuring may occur during range expansion. Ephemeral genetic structure can have important evolutionary implications, such as propagating genetic changes along the wave front of expansion, yet few studies have shown evidence of such structure. We tested the hypothesis that genetic structure arises during range expansion in Hemidactylus mabouia, a nocturnal African gecko recently introduced to Florida, USA. Twelve highly variable microsatellite loci were used to screen 418 individuals collected from 43 locations from four sampling sites across Florida, representing a gradient from earlier (∼1990s) to very recent colonization. We found earlier colonized locations had little detectable genetic structure and higher allelic richness than more recently colonized locations. Genetic structuring was pronounced among locations at spatial scales of tens to hundreds of meters near the leading edge of range expansion. Despite the rapid pace of range expansion in this introduced gecko, dispersal is limited among many suitable habitat patches. Fine-scale genetic structure is likely the result of founder effects during colonization of suitable habitat patches. It may be obscured over time and by scale-dependent modes of dispersal. Further studies are needed to determine if such genetic structure affects adaptation and trait evolution in range expansions and range shifts
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