174 research outputs found

    Beyond information seeking: towards a general model of information behaviour.

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    Introduction. The aim of the paper is to review models of information behaviour and to propose new models that extend the concept beyond simply information seeking to consider other modes of behaviour. The models chiefly explored are those of Wilson and Dervin. Argument A shortcoming of some models of information behaviour is that they present a sequence of stages in that behaviour and it is evident that actual behaviour is not always explained effectively by stages in a sequence. Development. A model of 'multi-directionality' is explored, to overcome the notion of sequential stages and, using Dervin's concept of 'the gap', modes of information behaviour are developed that include, for example, creating, destroying and avoiding information as well as seeking it. Conclusion. New models of information behaviour are presented that: replace the notion of 'barriers' with the concept of 'gap', as a means of integrating the views of Wilson and Dervin; incorporate the notion of multi-directionality; and identify ways in which an individual may navigate 'the gap' using different modes of information behaviour

    The impact of ocean acidification on the functional morphology of foraminifera

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    This work was supported by the NERC UK Ocean Acidification Research Programme grant NE/H017445/1. WENA acknowledges NERC support (NE/G018502/1). DMP received funding from the MASTS pooling initiative (The Marine Alliance for Science and Technology for Scotland). MASTS is funded by the Scottish Funding Council (grant reference HR09011) and contributing institutions.Culturing experiments were performed on sediment samples from the Ythan Estuary, N. E. Scotland, to assess the impacts of ocean acidification on test surface ornamentation in the benthic foraminifer Haynesina germanica. Specimens were cultured for 36 weeks at either 380, 750 or 1000 ppm atmospheric CO2. Analysis of the test surface using SEM imaging reveals sensitivity of functionally important ornamentation associated with feeding to changing seawater CO2 levels. Specimens incubated at high CO2 levels displayed evidence of shell dissolution, a significant reduction and deformation of ornamentation. It is clear that these calcifying organisms are likely to be vulnerable to ocean acidification. A reduction in functionally important ornamentation could lead to a reduction in feeding efficiency with consequent impacts on this organism’s survival and fitness.Publisher PDFPeer reviewe

    Organism-sediment interactions govern post-hypoxia recovery of ecosystem functioning

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    Hypoxia represents one of the major causes of biodiversity and ecosystem functioning loss for coastal waters. Since eutrophication-induced hypoxic events are becoming increasingly frequent and intense, understanding the response of ecosystems to hypoxia is of primary importance to understand and predict the stability of ecosystem functioning. Such ecological stability may greatly depend on the recovery patterns of communities and the return time of the system properties associated to these patterns. Here, we have examined how the reassembly of a benthic community contributed to the recovery of ecosystem functioning following experimentally-induced hypoxia in a tidal flat. We demonstrate that organism-sediment interactions that depend on organism size and relate to mobility traits and sediment reworking capacities are generally more important than recovering species richness to set the return time of the measured sediment processes and properties. Specifically, increasing macrofauna bioturbation potential during community reassembly significantly contributed to the recovery of sediment processes and properties such as denitrification, bedload sediment transport, primary production and deep pore water ammonium concentration. Such bioturbation potential was due to the replacement of the small-sized organisms that recolonised at early stages by large-sized bioturbating organisms, which had a disproportionately stronger influence on sediment. This study suggests that the complete recovery of organism-sediment interactions is a necessary condition for ecosystem functioning recovery, and that such process requires long periods after disturbance due to the slow growth of juveniles into adult stages involved in these interactions. Consequently, repeated episodes of disturbance at intervals smaller than the time needed for the system to fully recover organism-sediment interactions may greatly impair the resilience of ecosystem functioning.

    Characterizations of how species mediate ecosystem properties require more comprehensive functional effect descriptors

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    The importance of individual species in mediating ecosystem process and functioning is generally accepted, but categorical descriptors that summarize species-specific contributions to ecosystems tend to reference a limited number of biological traits and underestimate the importance of how organisms interact with their environment. Here, we show how three functionally contrasting sediment-dwelling marine invertebrates affect fluid and particle transport - important processes in mediating nutrient cycling - and use high-resolution reconstructions of burrow geometry to determine the extent and nature of biogenic modification. We find that individual functional effect descriptors fall short of being able to adequately characterize how species mediate the stocks and flows of important ecosystem properties and that, in contrary to common practice and understanding, they are not substitutable with one another because they emphasize different aspects of species activity and behavior. When information derived from these metrics is combined with knowledge of how species behave and modify their environment, however, detailed mechanistic information emerges that increases the likelihood that a species functional standing will be appropriately summarized. Our study provides evidence that more comprehensive functional effect descriptors are required if they are to be of value to those tasked with projecting how altered biodiversity will influence future ecosystems

    The geoaccumulation index and enrichment factor of mercury in mangrove sediment of Port Klang, Selangor, Malaysia.

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    Mangrove areas are important to the ecosystem. One of its crucial functions is as a sink of pollutants, especially metal ions. However, the accumulation of metals in mangrove sediment can generate negative impacts on plant growth, microbial activity, and soil fertility. Apart from that, the severity of the impact is highly influenced by the type of metal found in the sediment and the quality of sediment itself. One of the metals that have adverse effects on the environment is mercury. The objectives of this study are to determine the concentration and distribution of mercury and to assess the enrichment of mercury in Port Klang mangrove sediment by using geoaccumulation index and enrichment factor. Sediment samples were collected from 30 sampling points that cover Langat River and Klang River estuaries, Lumut Straits, Pulau Klang, and Pulau Indah. During sampling, water parameters such as pH, salinity, electrical conductivity, and total dissolved solids were measured in situ, whereas the total mercury in sediment samples was determined at the laboratory using inductively coupled plasma mass spectrometry. In this study, mercury was found to be concentrated along Lumut Strait especially in the mixing zone near the confluence of Langat River and at the jetty to Pulau Ketam. The geoaccumulation index and enrichment factor (calculated using logarithmized data of the reference element) found that three stations were enriched with mercury. In addition, geoaccumulation index was also observed to be more objective compared to enrichment factor whose results were influenced by the concentration of reference element used

    Modulation of endogenous antioxidant defense and the progression of kidney disease in multi-heritage groups of patients with type 2 diabetes: PRospective EValuation of Early Nephropathy and its Treatment (PREVENT).

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    BACKGROUND: Diabetes is the western world's leading cause of end-stage renal disease. Glucose-dependent, oxidative stress is linked to the development of renal inflammation and sclerosis, which, in animal models of diabetes, can be prevented by anti-oxidative treatment. Patients of non-Caucasian heritage have low activity of the selenoprotein, antioxidant enzyme, glutathione peroxidase (GPx) and its co-factor vitamin E, which may be linked to their increased propensity to developing end-stage renal disease. RESEARCH DESIGN AND METHODS: We have designed a double-blind, randomized, placebo controlled study with selenium and/or vitamin E versus placebo as the interventions for patients with type 2 diabetes and chronic kidney disease (CKD) stages 1-3. A 2 × 2 factorial design will allow a balanced representation of the heritage groups exposed to each intervention. The primary biochemical outcome is change in GPx activity, and clinical outcome measure is the actual, rate of-and/or percentage change in estimated glomerular filtration rate (eGFR) from baseline. Analysis will be with a marginal model for longitudinal data using Generalized Estimating Equations corrected for measures of baseline serum antioxidant enzyme activities (GPx, superoxide dismutase and catalase), micronutrient levels (vitamins E and C), measures of inflammation (interleukin 6, c-reactive protein and monocyte chemoattractant protein-1) and markers of oxidative damage (plasma 8-isoprostaglandin F2α and urinary 8-hydroxydeoxyguanosine). EXPECTED RESULTS: The study will assess the relationship between GPx activity, oxidative stress, inflammation and eGFR. It will test the null hypothesis that antioxidant therapy does not influence the activity of GPx or other antioxidant enzymes and/or alter the rate of change in eGFR in these patient groups. CONCLUSIONS: Outcome data on the effect of antioxidants in human diabetic renal disease is limited. Previous post hoc analyses have not shown a beneficial effect of vitamin E on renal function. A recent trial of a pharmaceutical antioxidant agent, improved eGFR, but in patients with advanced diabetes-related chronic kidney disease its use was associated with an increased incidence of cardiovascular events. We will explore whether the nutritional antioxidants, vitamin E and selenium alone, or in combination in patients at high risk of renal disease progression, forestalls a reduction in eGFR. The study will describe whether endogenous antioxidant enzyme defenses can be safely modified by this intervention and how this is associated with changes in markers of oxidative stress. Trial registration ISRCTN 97358113. Registered 21st September 2009

    Influence of firm size on the competencies required to management engineers in the Jordanian telecommunications sector

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    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

    Nutrient Enrichment and Food Web Composition Affect Ecosystem Metabolism in an Experimental Seagrass Habitat

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    Food web composition and resource levels can influence ecosystem properties such as productivity and elemental cycles. In particular, herbivores occupy a central place in food webs as the species richness and composition of this trophic level may simultaneously influence the transmission of resource and predator effects to higher and lower trophic levels, respectively. Yet, these interactions are poorly understood.Using an experimental seagrass mesocosm system, we factorially manipulated water column nutrient concentrations, food chain length, and diversity of crustacean grazers to address two questions: (1) Does food web composition modulate the effects of nutrient enrichment on plant and grazer biomasses and stoichiometry? (2) Do ecosystem fluxes of dissolved oxygen and nutrients more closely reflect above-ground biomass and community structure or sediment processes? Nutrient enrichment and grazer presence generally had strong effects on biomass accumulation, stoichiometry, and ecosystem fluxes, whereas predator effects were weaker or absent. Nutrient enrichment had little effect on producer biomass or net ecosystem production but strongly increased seagrass nutrient content, ecosystem flux rates, and grazer secondary production, suggesting that enhanced production was efficiently transferred from producers to herbivores. Gross ecosystem production (oxygen evolution) correlated positively with above-ground plant biomass, whereas inorganic nutrient fluxes were unrelated to plant or grazer biomasses, suggesting dominance by sediment microbial processes. Finally, grazer richness significantly stabilized ecosystem processes, as predators decreased ecosystem production and respiration only in the zero- and one- species grazer treatments.Overall, our results indicate that consumer presence and species composition strongly influence ecosystem responses to nutrient enrichment, and that increasing herbivore diversity can stabilize ecosystem flux rates in the face of perturbations
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