51 research outputs found
Effects of application of phosphorus fertilizer on brown blotch disease of cowpea
A field experiment was conducted to investigate the effects of level of phosphorus application on brown blotch disease of cowpea during the planting seasons of 2001, 2002 and 2003. Application of phosphorus from Single Super Phosphate at 30, 60, 90, and 120 kg P2O5/ha significantly increased the number of petioles, pods, nodules, seed/pod leaf area and yield. The higher the level of application of phosphorus the higher values of all the parameters. Disease incidence and severity of brown blotch were significantly reduced at higher levels of phosphorus (90 and 120 kg/ha) irrespective of the method of application. Moreover, there were also increases in the grain yield of cowpeaKeywords: Cowpea, disease phosphorus, levels, method
Problematic social media use: results from a large-scale nationally representative adolescent sample
Despite social media use being one of the most popular activities among adolescents, prevalence estimates among teenage samples of social media (problematic) use are lacking in the field. The present study surveyed a nationally representative Hungarian sample comprising 5,961 adolescents as part of the European School Survey Project on Alcohol and Other Drugs (ESPAD). Using the Bergen Social Media Addiction Scale (BSMAS) and based on latent profile analysis, 4.5% of the adolescents belonged to the at-risk group, and reported low self-esteem, high level of depression symptoms, and elevated social media use. Results also demonstrated that BSMAS has appropriate psychometric properties. It is concluded that adolescents at-risk of problematic social media use should be targeted by school-based prevention and intervention programs
Trait emotional intelligence and problematic social media use among adults: the mediating role of social media use motives
There are many contributing factors to problematic social media use including personality differences, psychosocial factors, and specific use motivations. The present study (N = 444 emerging adults, 75% women) investigated the direct and indirect relationships between trait emotional intelligence and problematic social media use via social media use motives by testing a complex mediation model. Path analyses suggested that trait emotional intelligence was directly and indirectly associated with problematic social media use via two social media use motives: (i) expressing or presenting a more popular self, and (ii) passing time. Results of the present study indicate that trait emotional intelligence may have a role in the motives for using social media as well as the development and maintenance of problematic social media use. Moreover, future studies should focus mediator risk factors between trait emotional intelligence and problematic social media use
Blockchain research, practice and policy: Applications, benefits, limitations, emerging research themes and research agenda
YesThe blockchain has received significant attention from technology focussed researchers, highlighting its perceived impact and emerging disruption potential, but has been slow to engender any significant momentum within the Information Systems (IS) and Information Management (IM) literature. This study approaches the subject through an IS/IM lens developing the key themes from the blockchain based research via a comprehensive review. This analysis of the body of literature highlights that although few commercial grade blockchain applications currently exist, the technology demonstrates significant potential to benefit a number of industry wide use cases. This study expands on this point articulating through each of the key themes to develop a detailed narrative on the numerous potential blockchain applications and future direction of the technology, whilst discussing the many barriers to adoption. The study asserts that blockchain technology has the potential to contribute to a number of the UN Sustainability Development Goals and engender widespread change within a number of established industries and practices
Cassava brown streak disease: historical timeline, current knowledge and future prospects
Cassava is the second most important staple food crop in terms of per capita calories consumed in Africa and holds potential for climate change adaptation. Unfortunately, productivity in East and Central Africa is severely constrained by two viral diseases: cassava mosaic disease (CMD) and cassava brown streak disease (CBSD). CBSD was first reported in 1936 from northeast Tanzania. For approximately seventy years CBSD was restricted to coastal East Africa and so had a relatively low impact on food security compared to CMD. However, at the turn of the 21st century CBSD re-emerged further inland, in areas around Lake Victoria and it has since spread through many East and Central African countries, causing high yield losses and jeopardising the food security of subsistence farmers. This recent re-emergence has attracted intense scientific interest, with studies shedding light on CBSD viral epidemiology, sequence diversity, host interactions and potential sources of resistance within the cassava genome. This review reflects on 80 years of CBSD research history (1936 – 2016) with a timeline of key events. We provide insights into current CBSD knowledge, management efforts and future prospects for improved understanding needed to underpin effective control and mitigation of impacts on food security
An overview of chemical additives present in plastics: Migration, release, fate and environmental impact during their use, disposal and recycling
Over the last 60 years plastics production has increased manifold, owing to their inexpensive, multipurpose, durable and lightweight nature. These characteristics have raised the demand for plastic materials that will continue to grow over the coming years. However, with increased plastic materials production, comes increased plastic material wastage creating a number of challenges, as well as opportunities to the waste management industry. The present overview highlights the waste management and pollution challenges, emphasising on the various chemical substances (known as “additives”) contained in all plastic products for enhancing polymer properties and prolonging their life. Despite how useful these additives are in the functionality of polymer products, their potential to contaminate soil, air, water and food is widely documented in literature and described herein. These additives can potentially migrate and undesirably lead to human exposure via e.g. food contact materials, such as packaging. They can, also, be released from plastics during the various recycling and recovery processes and from the products produced from recyclates. Thus, sound recycling has to be performed in such a way as to ensure that emission of substances of high concern and contamination of recycled products is avoided, ensuring environmental and human health protection, at all times
Ultra-High-Performance Concrete (UHPC) Use in Florida Structural Applications
In order for UHPC to be implemented in Florida structures and realize its potential benefits, research was needed to develop specifications for UHPC materials not supplied as prebagged materials. The research objective of this project was to establish mixing, placing, curing and durability requirements and test methods necessary to produce durable, non-proprietary UHPC, made using locally-sourced raw materials, for different classes of structural use and exposure conditions. This research program was performed using four different concrete mixture designs with different fiber contents and three different curing methods to investigate the range of material properties possible and their impact on strength, durability, and applicability of methods. As part of this work, a new modified double punch test was developed and is recommended for use in quality control, with direct tension testing recommended for mixture qualification. All mixtures with compressive strength above 15 ksi performed excellent in freeze-thaw testing. Steam curing was found to differentiate between good and worse performance of concrete microstructure for transport property testing. It is recommended that the UHPC fresh chloride limit be raised by 25% from 0.4 lb/yd3 to 0.5 lb/yd3. A modified rapid chloride migration test is recommended to be used on steam-cured samples with a chloride intrusion limit of 5 mm after 7 days. Steam curing samples gave conservative results at 28 days compared to the long-term test results and is recommended for acceptance testing purposes. A nondestructive electromagnetic sensor based on inductive principles quantify the fiber orientation in UHPC can be used in both lab and fields
From coloring the academic landscape to integral players of the community: Underrepresented minority librarians flexing their service muscles
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