Search results for: Karel Botha
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 21

Search results for: Karel Botha

21 Exploring the Process of Change in the Identity Constructs of Adolescents Exposed to Family Violence

Authors: Charlene Petersen, Herman Grobler, Karel Botha

Abstract:

Exposure to family violence has an impact on adolescent development, more specifically the identity process. This article explores the process of change in identity constructs of adolescents’ exposed to family violence in a Cape Town community in South Africa. In order to understand the process of identity formation the article explores and describes how the meaning that these adolescents give to family violence can contribute to change in their identity constructs. A mixed method approached was used in the study. A psycho-education strategy was implemented as the intervention and pretest-post-test scales were used to assess for change after the intervention process. Twelve participants were purposely selected for the study and included both male and female adolescents with ages ranging from 15 to 18 years from three secondary schools. The research data for this article were mainly extracted from the pre-test post-test design and the psycho-education strategy of the overall research study. The research results of the psycho-education strategy were thematically analyzed and a statistical procedure was used to measure for significant change within pre-test-post-test scales. The research merely refers to the outcome of psycho-education strategy and how it correlates with the outcome of the pre-test post-test design. Adolescents’ exposure to a psycho-education strategy, as well the pre-test post-test findings reveal a change within identity construct in terms of how they perceive themselves and interaction with others in the context of family violence.

Keywords: process of change in adolescent identity, family violence, psycho-education strategy, pre and post assessment

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20 A Psycho-Education Strategy as a Method for Reconstructing Identity in the Context of Family Violence

Authors: Charlene Petersen, Herman Grobler, Karel Botha

Abstract:

Restorative intervention with adolescents from a family violence context is a much needed resource given the limited access to mental health services in South Africa. In this research article the qualitative component which formed part of a mixed methods design of an overall research study, is discussed. A qualitative case study design was used. This article explores a psycho-education strategy, using a visual creative medium as a method for reconstructing identity in the context of family violence. The aim of this psycho-education strategy was to move away from interventions based on the biomedical model, but focused more on meaning-making about violent traumatic events adolescents have experienced, and to develop more positive, adaptive views about themselves in the present, and experience hope about the future. The research question that was asked was how the meaning, that adolescents from a specific community in South Africa give to family violence, contribute to defining their identity? Twelve participants were purposively selected for the study and included both male and female adolescents with ages ranging from 15 to 18 years from three secondary schools. The strategy was applied over five sessions with the intention to bring about awareness of different selves, identifying and naming the selves, and becoming aware of the configuration of identity that could lead to a redefined identity. The data were thematically and visually analyzed. Through the process of tailoring which forms the basis for reconstruction process, participants could identify the different selves, become aware of how they configure in the field. Through the process of tailoring the different self-parts, the sense of self became more self-cohesive and allowed the individual to become aware of the role of certain. Through identifying and naming the future self and resilient self the participants were able to accomplish some order and meaning in their lives. It provided them with a sense of predictability and an optimistic and hopefulness towards the future. The research findings indicated that this strategy can be used as a method for reconstructing identity in the context of family violence.

Keywords: identity, family violence, self-configuration, reconstructing identity, psycho-education strategy

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19 Support of Knowledge Sharing in Manufacturing Companies: A Case Study

Authors: Zuzana Crhová, Karel Kolman, Drahomíra Pavelková

Abstract:

Knowledge is considered as an important asset which can help organizations to create competitive advantage. The necessity of taking care of these assets is more important in these days – in days of turbulent changes in business environment. Knowledge could facilitate adaption to constant changes. The aim of this paper is to describe how the knowledge sharing can be supported in the manufacturing companies. The methods of case studies and grounded theory were used to present information gained by carrying out semi-structured interviews. Results show that knowledge sharing is supported in very similar ways in respondent companies.

Keywords: case study, human resource management, knowledge, knowledge sharing

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18 Condensation of Moist Air in Heat Exchanger Using CFD

Authors: Jan Barak, Karel Frana, Joerg Stiller

Abstract:

This work presents results of moist air condensation in heat exchanger. It describes theoretical knowledge and definition of moist air. Model with geometry of square canal was created for better understanding and post processing of condensation phenomena. Different approaches were examined on this model to find suitable software and model. Obtained knowledge was applied to geometry of real heat exchanger and results from experiment were compared with numerical results. One of the goals is to solve this issue without creating any user defined function in the applied code. It also contains summary of knowledge and outlook for future work.

Keywords: condensation, exchanger, experiment, validation

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17 Tests and Comparison of Two Mobile Industrial Analytical Systems for Mercury Speciation in Flue Gas

Authors: Karel Borovec, Jerzy Gorecki, Tadeas Ochodek

Abstract:

Combustion of solid fuels is one of the main sources of mercury in the environment. To reduce the amount of mercury emitted to the atmosphere, it is necessary to modify or optimize old purification technologies or introduce the new ones. Effective reduction of mercury level in the flue gas requires the use of speciation systems for mercury form determination. This paper describes tests and provides comparison of two industrial portable and continuous systems for mercury speciation in the flue gas: Durag HM-1400 TRX with a speciation module and the Portable Continuous Mercury Speciation System based on the SGM-8 mercury speciation set, made by Nippon Instruments Corporation. Additionally, the paper describes a few analytical problems that were encountered during a two-year period of using the systems.

Keywords: continuous measurement, flue gas, mercury determination, speciation

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16 Air Flows along Perforated Metal Plates with the Heat Transfer

Authors: Karel Frana, Sylvio Simon

Abstract:

The objective of the paper is a numerical study of heat transfer between perforated metal plates and the surrounding air flows. Different perforation structures can nowadays be found in various industrial products. Besides improving the mechanical properties, the perforations can intensify the heat transfer as well. The heat transfer coefficient depends on a wide range of parameters such as type of perforation, size, shape, flow properties of the surrounding air etc. The paper was focused on three different perforation structures which have been investigated from the point of the view of the production in the previous studies. To determine the heat coefficients and the Nusselt numbers, the numerical simulation approach was adopted. The calculations were performed using the OpenFOAM software. The three-dimensional, unstable, turbulent and incompressible air flow around the perforated surface metal plate was considered.

Keywords: perforations, convective heat transfers, turbulent flows, numerical simulations

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15 A Qualitative Case Study Exploring Zambian Mathematics Teachers' Content Knowledge of Functions

Authors: Priestly Malambo, Sonja Van Putten, Hanlie Botha, Gerrit Stols

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The relevance of what is content is taught in tertiary teacher training has long been in question. This study attempts to understand how advanced mathematics courses equip student teachers to teach functions at secondary school level. This paper reports on an investigation that was conducted in an African university, where preservice teachers were purposefully selected for participation in individual semi-structured interviews after completing a test on functions as taught at secondary school. They were asked to justify their reasoning in the test and to explain functions in a way that might bring about understanding of the topic in someone who did not know how functions work. These were final year preservice mathematics teachers who had studied advanced mathematics courses for three years. More than 50% of the students were not able to explain concepts or to justify their reasoning about secondary school functions in a coherent way. The results of this study suggest that the study of advanced mathematics does not automatically enable students to teach secondary school functions, and that, although these students were able to do advanced mathematics, they were unable to explain the working of functions in a way that would allow them to teach this topic successfully.

Keywords: secondary school, mathematical reasoning, student-teachers, functions

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14 Spatially Encoded Hyperspectral Compressive Microscope for Broadband VIS/NIR Imaging

Authors: Lukáš Klein, Karel Žídek

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Hyperspectral imaging counts among the most frequently used multidimensional sensing methods. While there are many approaches to capturing a hyperspectral data cube, optical compression is emerging as a valuable tool to reduce the setup complexity and the amount of data storage needed. Hyperspectral compressive imagers have been created in the past; however, they have primarily focused on relatively narrow sections of the electromagnetic spectrum. A broader spectral study of samples can provide helpful information, especially for applications involving the harmonic generation and advanced material characterizations. We demonstrate a broadband hyperspectral microscope based on the single-pixel camera principle. Captured spatially encoded data are processed to reconstruct a hyperspectral cube in a combined visible and near-infrared spectrum (from 400 to 2500 nm). Hyperspectral cubes can be reconstructed with a spectral resolution of up to 3 nm and spatial resolution of up to 7 µm (subject to diffraction) with a high compressive ratio.

Keywords: compressive imaging, hyperspectral imaging, near-infrared spectrum, single-pixel camera, visible spectrum

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13 Data Integrity: Challenges in Health Information Systems in South Africa

Authors: T. Thulare, M. Herselman, A. Botha

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Poor system use, including inappropriate design of health information systems, causes difficulties in communication with patients and increased time spent by healthcare professionals in recording the necessary health information for medical records. System features like pop-up reminders, complex menus, and poor user interfaces can make medical records far more time consuming than paper cards as well as affect decision-making processes. Although errors associated with health information and their real and likely effect on the quality of care and patient safety have been documented for many years, more research is needed to measure the occurrence of these errors and determine the causes to implement solutions. Therefore, the purpose of this paper is to identify data integrity challenges in hospital information systems through a scoping review and based on the results provide recommendations on how to manage these. Only 34 papers were found to be most suitable out of 297 publications initially identified in the field. The results indicated that human and computerized systems are the most common challenges associated with data integrity and factors such as policy, environment, health workforce, and lack of awareness attribute to these challenges but if measures are taken the data integrity challenges can be managed.

Keywords: data integrity, data integrity challenges, hospital information systems, South Africa

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12 Interoperability Maturity Models for Consideration When Using School Management Systems in South Africa: A Scoping Review

Authors: Keneilwe Maremi, Marlien Herselman, Adele Botha

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The main purpose and focus of this paper are to determine the Interoperability Maturity Models to consider when using School Management Systems (SMS). The importance of this is to inform and help schools with knowing which Interoperability Maturity Model is best suited for their SMS. To address the purpose, this paper will apply a scoping review to ensure that all aspects are provided. The scoping review will include papers written from 2012-2019 and a comparison of the different types of Interoperability Maturity Models will be discussed in detail, which includes the background information, the levels of interoperability, and area for consideration in each Maturity Model. The literature was obtained from the following databases: IEEE Xplore and Scopus, the following search engines were used: Harzings, and Google Scholar. The topic of the paper was used as a search term for the literature and the term ‘Interoperability Maturity Models’ was used as a keyword. The data were analyzed in terms of the definition of Interoperability, Interoperability Maturity Models, and levels of interoperability. The results provide a table that shows the focus area of concern for each Maturity Model (based on the scoping review where only 24 papers were found to be best suited for the paper out of 740 publications initially identified in the field). This resulted in the most discussed Interoperability Maturity Model for consideration (Information Systems Interoperability Maturity Model (ISIMM) and Organizational Interoperability Maturity Model for C2 (OIM)).

Keywords: interoperability, interoperability maturity model, school management system, scoping review

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11 Educating the Education Student: Technology as the Link between Theory and Praxis

Authors: Rochelle Botha-Marais

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When lecturing future educators in South Africa, praxis is an indispensable aspect that is often neglected. Without properly understanding how the theory taught in lecture halls relates to their future position as educators, we can not expect these students to be fully equipped future teachers. To enable education students at the Vaal Campus of the North West University - who have the Afrikaans language as major - to discover the link between theory and practice, the author created an assignment on phonetics in which the use of technology was incorporated. In the past, students had to submit an assignment or worksheet and they did not get the opportunity to apply their newly found knowledge in a practical manner. For potential future teachers, this application is essential. This paper will demonstrate how technology is used in the second year Afrikaans education module to promote student engagement and self-directed learning. Students were introduced to innovative new technologies alongside more familiar applications to shape a 21st century learning environment where students can think, communicate, solve problems, collaborate and take responsibility for their own teaching and learning. The paper will also reflect on student feedback pertaining the use and efficiency of technology in the Afrikaans module and the possible impact thereof on their own teaching and learning landscape. The aim of this paper is to showcase how technology can be used to maximize the students learning experience and equip future education students with the tools and knowledge to introduce technology-enhanced learning in their own teaching practice.

Keywords: education students, theory and practice, self-directed learning, student engagement, technology

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10 A Socio-Cultural Approach to Implementing Inclusive Education in South Africa

Authors: Louis Botha

Abstract:

Since the presentation of South Africa’s inclusive education strategy in Education White Paper 6 in 2001, very little has been accomplished in terms of its implementation. The failure to achieve the goals set by this policy document is related to teachers lacking confidence and knowledge about how to enact inclusive education, as well as challenges of inflexible curricula, limited resources in overcrowded classrooms, and so forth. This paper presents a socio-cultural approach to addressing these challenges of implementing inclusive education in the South African context. It takes its departure from the view that inclusive education has been adequately theorized and conceptualized in terms of its philosophical and ethical principles, especially in South African policy and debates. What is missing, however, are carefully theorized, practically implementable research interventions which can address the concerns mentioned above. Drawing on socio-cultural principles of learning and development and on cultural-historical activity theory (CHAT) in particular, this paper argues for the use of formative interventions which introduce appropriately constructed mediational artifacts that have the potential to initiate inclusive practices and pedagogies within South African schools and classrooms. It makes use of Vygotsky’s concept of double stimulation to show how the proposed artifacts could instigate forms of transformative agency which promote the adoption of inclusive cultures of learning and teaching.

Keywords: cultural-historical activity theory, double stimulation, formative interventions, transformative agency

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9 Improving Seat Comfort by Semi-Active Control of Magnetorheological Damper

Authors: Karel Šebesta, Jiří Žáček, Matuš Salva, Mohammad Housam

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Drivers of agricultural vehicles are exposed to continuous vibration caused by driving over rough terrain. The long-term effects of these vibrations could start with a decreased level of vigilance at work and could reach the level of several health problems. Therefore, eliminating the vibration to maximize the comfort of the driver is essential for better/longer performance. One of the modern damping systems, which can deal with this problem is the Semi-active (S/A) suspension system featuring a Magnetorheological (MR) damper. With this damper, the damping level can be adjusted using varying currents through the coil. Adjustments of the damping force can be carried out continuously based on the evaluated data (position and acceleration of seat) by the control algorithm. The advantage of this system is the wide dynamic range and the high speed of force response time. Compared to other S/A or active systems, the MR damper does not need as much electrical power, and the system is much simpler. This paper aims to prove the effectiveness of this damping system used in the tractor seat. The vibration testing stand was designed and manufactured specifically for this type of research, which is used to simulate vibrations with constant amplitude at variable frequency.

Keywords: magnetorheological damper, semi-active suspension, seat scissor mechanism, sky-hook

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8 Treatment of Leather Industry Wastewater with Advance Treatment Methods

Authors: Seval Yilmaz, Filiz Bayrakci Karel, Ali Savas Koparal

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Textile products produced by leather have been indispensable for human consumption. Various chemicals are used to enhance the durability of end-products in the processing of leather products. The wastewaters from the leather industry which contain these chemicals exhibit toxic effects on the receiving environment and threaten the natural ecosystem. In this study, leather industry wastewater (LIW), which has high loads of contaminants, was treated using advanced treatment techniques instead of conventional methods. During the experiments, the performance of electrochemical methods was investigated. During the electrochemical experiments, the performance of batch electrooxidation (EO) using boron-doped diamond (BDD) electrodes with monopolar configuration for removal of chemical oxygen demand (COD) from LIW were investigated. The influences of electrolysis time, current density (which varies as 5 mA/cm², 10 mA/cm², 20 mA/cm², 30 mA/cm², 50 mA/cm²) and initial pH (which varies as 3,80 (natural pH of LIW), 7, 9) on removal efficiency were investigated in a batch stirred cell to determine the best treatment conditions. The current density applied to the electrochemical reactors is directly proportional to the consumption of electric energy, so electrical energy consumption was monitored during the experiment. The best experimental conditions obtained in electrochemical studies were as follows: electrolysis time = 60 min, current density = 30.0 mA/cm², pH 7. Using these parameters, 53.59% COD removal rates for LIW was achieved and total energy consumption was obtained as 13.03 kWh/m³. It is concluded that electrooxidation process constitutes a plausible and developable method for the treatment of LIW.

Keywords: BDD electrodes, COD removal, electrochemical treatment, leather industry wastewater

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7 A Twelve-Week Intervention Programme to Improve the Gross Motor Skills of Selected Children Diagnosed with Autism Spectrum Disorder

Authors: Eileen K. Africa, Karel J. van Deventer

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Neuro-typical children develop the motor skills necessary to play, do schoolwork and interact with others. However, this is not observed in children who have learning or behavioural problems. Children with Autism Spectrum Disorder (ASD) are often referred to as clumsy because their body parts do not work well together in a sequence. Physical Activity (PA) has shown to be beneficial to the general population, therefore, providing children with ASD opportunities to take part in PA programmes, could prove to be beneficial in many ways and should be investigated. The purpose of this study was to design a specialised group intervention programme, to attempt to improve gross motor skills of selected children diagnosed with ASD between the ages of eight and 13 years. A government school for ASD learners was recruited to take part in this study, and a sample of convenience (N=7) was selected. Children in the experimental group (n=4) participated in a 12-week group intervention programme twice per week, while the control group continued with their normal daily routine. The Movement Assessment Battery for Children-Second Edition (MABC-2), was administered pre- and post-test to determine the children’s gross motor proficiency and to determine if the group intervention programme had an effect on the gross motor skills of the experimental group. Statistically significant improvements were observed in total motor skill proficiency (p < 0.05), of the experimental group. These results demonstrate the importance of gross motor skills interventions for children diagnosed with ASD. Future research should include more participants to ensure that the results can be generalised.

Keywords: autism spectrum disorder, children, gross motor skills, group intervention programme

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6 Expression Profiling and Immunohistochemical Analysis of Squamous Cell Carcinoma of Head and Neck (Tumor, Transition Zone, Normal) by Whole Genome Scale Sequencing

Authors: Veronika Zivicova, Petr Broz, Zdenek Fik, Alzbeta Mifkova, Jan Plzak, Zdenek Cada, Herbert Kaltner, Jana Fialova Kucerova, Hans-Joachim Gabius, Karel Smetana Jr.

Abstract:

The possibility to determine genome-wide expression profiles of cells and tissues opens a new level of analysis in the quest to define dysregulation in malignancy and thus identify new tumor markers. Toward this long-term aim, we here address two issues on this level for head and neck cancer specimen: i) defining profiles in different regions, i.e. the tumor, the transition zone and normal control and ii) comparing complete data sets for seven individual patients. Special focus in the flanking immunohistochemical part is given to adhesion/growth-regulatory galectins that upregulate chemo- and cytokine expression in an NF-κB-dependent manner, to these regulators and to markers of differentiation, i.e. keratins. The detailed listing of up- and down-regulations, also available in printed form (1), not only served to unveil new candidates for testing as marker but also let the impact of the tumor in the transition zone become apparent. The extent of interindividual variation raises a strong cautionary note on assuming uniformity of regulatory events, to be noted when considering therapeutic implications. Thus, a combination of test targets (and a network analysis for galectins and their downstream effectors) is (are) advised prior to reaching conclusions on further perspectives.

Keywords: galectins, genome scale sequencing, squamous cell carcinoma, transition zone

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5 The Digitalization of Occupational Health and Safety Training: A Fourth Industrial Revolution Perspective

Authors: Deonie Botha

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Digital transformation and the digitization of occupational health and safety training have grown exponentially due to a variety of contributing factors. The literature suggests that digitalization has numerous benefits but also has associated challenges. The aim of the paper is to develop an understanding of both the perceived benefits and challenges of digitalization in an occupational health and safety context in an effort to design and develop e-learning interventions that will optimize the benefits of digitalization and address the associated challenges. The paper proposes, deliberate and tests the design principles of an e-learning intervention to ensure alignment with the requirements of a digitally transformed environment. The results of the research are based on a literature review regarding the requirements and effect of the Fourth Industrial Revolution on learning and e-learning in particular. The findings of the literature review are enhanced with empirical research in the form of a case study conducted in an organization that designs and develops e-learning content in the occupational health and safety industry. The primary findings of the research indicated that: (i) The requirements of learners and organizations in respect of e-learning are different than previously (i.e., a pre-Fourth Industrial Revolution related work setting). (ii) The design principles of an e-learning intervention need to be aligned with the entire value chain of the organization. (iii) Digital twins support and enhance the design and development of e-learning. (iv)Learning should incorporate a multitude of sensory experiences and should not only be based on visual stimulation. (v) Data that are generated as a result of e-learning interventions should be incorporated into big data streams to be analyzed and to become actionable. It is therefore concluded that there is general consensus on the requirements that e-learning interventions need to adhere to in a digitally transformed occupational health and safety work environment. The challenge remains for organizations to incorporate data generated as a result of e-learning interventions into the digital ecosystem of the organization.

Keywords: digitalization, training, fourth industrial revolution, big data

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4 Preliminary Composite Overwrapped Pressure Vessel Design for Hydrogen Storage Using Netting Analysis and American Society of Mechanical Engineers Section X

Authors: Natasha Botha, Gary Corderely, Helen M. Inglis

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With the move to cleaner energy applications the transport industry is working towards on-board hydrogen, or compressed natural gas-fuelled vehicles. A popular method for storage is to use composite overwrapped pressure vessels (COPV) because of their high strength to weight ratios. The proper design of these COPVs are according to international standards; this study aims to provide a preliminary design for a 350 Bar Type IV COPV (i.e. a polymer liner with a composite overwrap). Netting analysis, a popular analytical approach, is used as a first step to generate an initial design concept for the composite winding. This design is further improved upon by following the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel standards, Section X: Fibre-reinforced composite pressure vessels. A design program based on these two approaches is developed using Python. A numerical model of a burst test simulation is developed based on the two approaches and compared. The results indicate that the netting analysis provides a good preliminary design, while the ASME-based design is more robust and accurate as it includes a better approximation of the material behaviour. Netting analysis is an easy method to follow when considering an initial concept design for the composite winding when not all the material characteristics are known. Once these characteristics have been fully defined with experimental testing, an ASME-based design should always be followed to ensure that all designs conform to international standards and practices. Future work entails more detailed numerical testing of the design for improvement, this will include the boss design. Once finalised prototype manufacturing and experimental testing will be conducted, and the results used to improve on the COPV design.

Keywords: composite overwrapped pressure vessel, netting analysis, design, American Society of Mechanical Engineers section x, fiber-reinforced, hydrogen storage

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3 Inhibitory Activity of Podospermum canum and Its Active Components on Collagenase, Elastase and Hyaluronidase Enzymes

Authors: Ozlem Bahadir Acikara, Mert Ilhan, Ekin Kurtul, Karel Smejkal, Esra Kupeli Akkol

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Present study is aimed to investigate in vitro inhibitory effects of the extracts prepared from the aerial parts of Podospermum canum (Asteraceae) on hyaluronidase, collagenase, and elastase enzymes using a bioassay-guided fractionation. Inhibitory effects of the extract, sub-extracts, fractions obtained by column chromatography, and isolated compounds on collagenase, elastase, and hyaluronidase were performed by using in vitro enzyme inhibitory assays based on spectrophotometric evaluation. The ethyl acetate and remaining water extracts prepared from the plant displayed significant inhibitory activities on collagenase and elastase, while petroleum ether and chloroform extracts did not show any inhibitory activity. Eleven known compounds: arbutin, 6'-O-caffeoylarbutin, cichoriin, 3,5-dicaffeoylquinic acid methyl ester, apigenin-7-O-β-glucoside, luteolin-7-O-β-glucoside, apigenin-7-O-β-rutinoside, isoorientin, orientin, vitexin, procatechuic acid, and compound 4-hydroxy-benzoic acid 4-(6-O-α-rhamnopyranosyl-β-glucopyranosyl) benzyl ester have been obtained from ethyl acetate sub-extract of the plant through bioassay-guided fractionation and isolation. Results of the present study have revealed that among the isolated compounds, apigenin-7-O-β-glucoside, luteolin-7-O-β-glucoside, apigenin-7-O-β-rutinoside and isoorientin showed potent enzyme inhibitory activities. However, methanolic extract of P. canum displayed a greater inhibitory activity than fractions and isolated compounds both on collagenase and elastase.

Keywords: Asteraceae, collagenase, elastase, hyaluronidase, Podospermum canum

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2 Raising Antibodies against Epoxyscillirosidine, the Toxic Principle Contained in Moraea pallida Bak. in Rabbits

Authors: Hamza I. Isa, Gezina C. H. Ferreira, Jan E. Crafford, Christoffel J. Botha

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Moraea pallida Bak. (yellow tulip) poisoning is the most important plant-induced cardiac glycoside toxicosis in South Africa. Cardiac glycoside poisonings collectively account for about 33 and 10 % mortalities due to plants, in large and small stock respectively, in South Africa. The toxic principle is 1α, 2α-epoxyscillirosidine, a bufadienolide. The aim of the study was to investigate the potential to develop a vaccine against epoxyscillirosidine. Epoxyscillirosidine and the related bufadienolides proscillaridin and bufalin, which are commercially available, were conjugated to the carrier proteins [Hen ovalbumin (OVA), bovine serum albumin (BSA) and keyhole limpet haemocyanin (KLH)], rendering them immunogenic. Adult male New Zealand White rabbits were immunized. In Trials 1 and 2, rabbits (n=6) were, each assigned to two groups. Experimental animals (n=3; n=4) were vaccinated with epoxyscillirosidine-OVA conjugate, while the control (n=3; n=2) were vaccinated with OVA, using Freund’s complete and incomplete and Montanide adjuvants, for Trials 1 and 2, respectively. In Trial 3, rabbits (n=15), randomly allocated to 5 equal groups (I, II, III, IV and V), were vaccinated with proscillaridin-BSA, bufalin-BSA, epoxyscillirosidine-KLH, epoxyscillirosidine-BSA conjugates, and BSA respectively, using Montanide as adjuvant. Vaccination was on Days 0, 21 and 42. Additional vaccinations were done on Day 56 and 63 for Trial 1. Vaccination was by intradermal injection of 0.4 ml of the immunogen (4 mg/ml [Trial 1] and 8 mg/ml for Trials 2 and Trial 3, respectively). Blood was collected pre-vaccination and at 3 week intervals following each vaccination. Antibody response was determined using an indirect ELISA. There was poor immune response associated with the dose (0.4 mg per rabbit) and adjuvant used in Trial 1. Antibodies were synthesized against the conjugate administered in Trial 2. For Trail 3, antibodies against the immunogens were successfully raised in rabbits with epoxyscillirosidine-KLH inducing the highest immune response. The antibodies raised against proscillaridin and bufalin cross-reacted with epoxyscillirosidine when used as antigen in the ELISA. The study successfully demonstrated the synthesis of antibodies against the bufadienolide conjugates administered. The cross-reactivity of proscillaridin and bufalin with epoxyscillirosidine could potentially be utilized as alternative to epoxyscillirosidine in future studies to prevent yellow tulp poisoning by vaccination.

Keywords: antibodies , bufadienolides, cross-reactivity, epoxyscillirosidine, Moraea pallida, poisoning

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1 Bundling of Transport Flows: Adoption Barriers and Opportunities

Authors: Vandenbroucke Karel, Georges Annabel, Schuurman Dimitri

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In the past years, bundling of transport flows, whether or not implemented in an intermodal process, has popped up as a promising concept in the logistics sector. Bundling of transport flows is a process where two or more shippers decide to synergize their shipped goods over a common transport lane. Promoted by the European Commission, several programs have been set up and have shown their benefits. Bundling promises both shippers and logistics service providers economic, societal and ecological benefits. By bundling transport flows and thus reducing truck (or other carrier) capacity, the problems of driver shortage, increased fuel prices, mileage charges and restricted hours of service on the road are solved. In theory, the advantages of bundled transport exceed the drawbacks, however, in practice adoption among shippers remains low. In fact, bundling is mentioned as a disruptive process in the rather traditional logistics sector. In this context, a Belgian company asked iMinds Living Labs to set up a Living Lab research project with the goal to investigate how the uptake of bundling transport flows can be accelerated and to check whether an online data sharing platform can overcome the adoption barriers. The Living Lab research was conducted in 2016 and combined quantitative and qualitative end-user and market research. Concretely, extensive desk research was conducted and combined with insights from expert interviews with four consultants active in the Belgian logistics sector and in-depth interviews with logistics professionals working for shippers (N=10) and LSP’s (N=3). In the article, we present findings which show that there are several factors slowing down the uptake of bundling transport flows. Shippers are hesitant to change how they currently work and they are hesitant to work together with other shippers. Moreover, several practical challenges impede shippers to work together. We also present some opportunities that can accelerate the adoption of bundling of transport flows. First, it seems that there is not enough support coming from governmental and commercial organizations. Secondly, there is the chicken and the egg problem: too few interested parties will lead to no or very few matching lanes. Shippers are therefore reluctant to partake in these projects because the benefits have not yet been proven. Thirdly, the incentive is not big enough for shippers. Road transport organized by the shipper individually is still seen as the easiest and cheapest solution. A solution for the abovementioned challenges might be found in the online data sharing platform of the Belgian company. The added value of this platform is showing shippers possible matching lanes, without the shippers having to invest time in negotiating and networking with other shippers and running the risk of not finding a match. The interviewed shippers and experts indicated that the online data sharing platform is a very promising concept which could accelerate the uptake of bundling of transport flows.

Keywords: adoption barriers, bundling of transport, shippers, transport optimization

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