Search results for: autonomous agents
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2084

Search results for: autonomous agents

524 Effect of Agricultural Extension Services on Technical Efficiency of Smallholder Cassava Farmers in Ghana: A Stochastic Meta-Frontier Analysis

Authors: Arnold Missiame

Abstract:

In Ghana, rural dwellers who depend primarily on agriculture for their livelihood constitute about 60% of the country’s population. This shows the critical role and potentials of the agricultural sector in helping to achieve Ghana’s vision 2030. With the current threat of climate change and advancements in technology, agricultural extension is not just about technology transfer and improvements in productivity, but it is also about improving the managerial and technical skills of farmers. In Ghana, the government of Ghana as well as other players in the sector like; non-governmental organizations, NGOs, local and international funding agencies, for decades now, have made capacity-building-investments in smallholder farmers by way of extension services delivery. This study sought to compare the technical efficiency of farmers who have access to agricultural extension and farmers who do not in Ghana. The study employed the stochastic meta-frontier model to analyze household survey data comprising 300 smallholder cassava farmers from the Fanteakwa district of Ghana. The farmers were selected through a two-stage sampling technique where 5 communities were purposively selected in the first stage and then 60 smallholder cassava farmers were randomly selected from each of the 5 communities. Semi-structured questionnaires were used to collect data on farmers’ socioeconomic and farm-level characteristics. The results showed that farmers who have access to agricultural extensions services have higher technical efficiencies (TE) and produce much closer to their meta-production frontiers (higher technology gap ratios (TGR) than farmers who do not have access to such extension services. Furthermore, experience in cassava cultivation and formal education significantly improves the technical efficiencies of farmers. The study recommends that the mode and scope of agricultural extension service delivery in the country should be enhanced to ensure that smallholder farmers have easy access to extension agents.

Keywords: agricultural extension, Ghana, smallholder farmers, stochastic meta-frontier model, technical efficiency

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523 Payload Bay Berthing of an Underwater Vehicle With Vertically Actuated Thrusters

Authors: Zachary Cooper-Baldock, Paulo E. Santos, Russell S. A. Brinkworth, Karl Sammut

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In recent years, large unmanned underwater vehicles such as the Boeing Voyager and Anduril Ghost Shark have been developed. These vessels can be structured to contain onboard internal payload bays. These payload bays can serve a variety of purposes – including the launch and recovery (LAR) of smaller underwater vehicles. The LAR of smaller vessels is extremely important, as it enables transportation over greater distances, increased time on station, data transmission and operational safety. The larger vessel and its payload bay structure complicate the LAR of UUVs in contrast to static docks that are affixed to the seafloor, as they actively impact the local flow field. These flow field impacts require analysis to determine if UUV vessels can be safely launched and recovered inside the motherships. This research seeks to determine the hydrodynamic forces exerted on a vertically over-actuated, small, unmanned underwater vehicle (OUUV) during an internal LAR manoeuvre and compare this to an under-actuated vessel (UUUV). In this manoeuvre, the OUUV is navigated through the stern wake region of the larger vessel to a set point within the internal payload bay. The manoeuvre is simulated using ANSYS Fluent computational fluid dynamics models, covering the entire recovery of the OUUV and UUUV. The analysis of the OUUV is compared against the UUUV to determine the differences in the exerted forces. Of particular interest are the drag, pressure, turbulence and flow field effects exerted as the OUUV is driven inside the payload bay of the larger vessel. The hydrodynamic forces and flow field disturbances are used to determine the feasibility of making such an approach. From the simulations, it was determined that there was no significant detrimental physical forces, particularly with regard to turbulence. The flow field effects exerted by the OUUV are significant. The vertical thrusters exert significant wake structures, but their orientation ensures the wake effects are exerted below the UUV, minimising the impact. It was also seen that OUUV experiences higher drag forces compared to the UUUV, which will correlate to an increased energy expenditure. This investigation found no key indicators that recovery via a mothership payload bay was not feasible. The turbulence, drag and pressure phenomenon were of a similar magnitude to existing static and towed dock structures.

Keywords: underwater vehicles, submarine, autonomous underwater vehicles, AUV, computational fluid dynamics, flow fields, pressure, turbulence, drag

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522 Adoption of Risk and Insurance among Aquaculture Producers in Khuzestan Province, Iran

Authors: Kiyanoush Ghalavand

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Aquaculture production is inherently a risky business, and farmers face a variety of weather, pest, disease, inptut supply, and market related risks. There are many factors out farmers control and unpredictable. Insurance has an important role in aquaculture production and is a tool to support farmers against threats. Investigation of factors affecting aquaculture farmers' adoption of aquaculture insurance strategy was the objective of this study. The purpose of this study was determining the related factors to adoption of insurance by aquaculture farmers in Khuzestan province, Iran. The research design was a descriptive and correlation surveying method. Aquaculture farmers in Khuzestan province were the target population for this study. A random sample of aquaculture selected (N=1830, n =139). The main result of the study reveled that exist correlation between the level of education, knowledge about purpose of insurance, participation in extension course, visit with insurance organization, and contact with extension agents to the adoption of insurance by aquaculture farmers were significantly positive. By using Bartlett's test and KMO test, determine whether research variables are appropriate for factor analysis (Sig = 0.000, Bartlett test = 0.9724, KMO = 0.74). The number of factors was determined using a split plot, eigenvalue, and percent of variance. An examination of the items and their factors loadings was used to understand the nature of the nine factors. To reduce subjectivity, items with factor loading equal to or greater than 0.5 were considered most important when factors were labeled. The nine factors were labeled (1) Extension and education activities, (2) Economical characteristics, (3) Governmental support, (4) communicational channel, (5) local leaders, (6) Facilitate in given damage (7) Motivation establishing, (8) Given damage in appropriate methods and (9) Appropriate activities by insurance organization. The results obtained from the factors analysis reveal that the nine factors explain percentage75 of the variation of the adoption of insurance of the adoption of insurance by aquaculture farmers in Khuzestan province.

Keywords: aquaculture farmers, insurance, factorial analysis, Khuzestan province, risks

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521 Identification and Application of Biocontrol Agents against Cotton Leaf Curl Virus Disease in Gossypium hirsutum under Green House Conditions

Authors: Memoona Ramzan, Bushra Tabassum, Anwar Khan, Muhammad Tariq, Mudassar Fareed Awan, Idrees Ahmad Nasir, Zahida Qamar, Naila Shahid, Tayyab Husnain

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Biological control is a novel approach being used in crop protection nowadays. Bacteria like Bacillus and Pseudomonas are reported for this purpose and few of their products are commercially available too. Rhizosphere and phyllosphere of healthy cotton plants were used as a source to isolate bacteria capable of exhibiting properties worthy for selection as biocontrol agent. For this purpose all isolated strains were screened for the activities like phosphate solubilization, Indole acetic acid (IAA) production and biocontrol against fungi. Two strains S1HL3 and S1HL4 showed phosphate solubilization and IAA production simultaneously while two other JS2HR4 and JS3HR2 were good inhibitors of fungal pathogens. Through biochemical and molecular characterization these bacteria were identified as P. aeruginosa, Burkholderia and Bacillus respectively. In green house trials of these isolates against Cotton leaf curl virus (CLCuV), seven treatments including individual bacterial isolate and consortia were included. Treated plants were healthy as compared to control plants in which upto 74% CLCuV symptomatic plants exist. Maximum inhibition of CLCuV was observed in T7 treated plants where viral load was only 0.4% as compared to control where viral load was upto 74%. This treatment consortium included Bacillus and Pseudomonas isolates; S1HL3, S1HL4, JS2HR4 and JS3HR2. Principal Component Biplot depicted highly significant correlation between percentage viral load and the disease incidence.

Keywords: cotton leaf curl virus, biological control, bacillus, pseudomonas

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520 Total Synthesis of Natural Cyclic Depsi Peptides by Convergent SPPS and Macrolactonization Strategy for Anti-Tb Activity

Authors: Katharigatta N. Venugopala, Fernando Albericio, Bander E. Al-Dhubiab, T. Govender

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Recent years have witnessed a renaissance in the field of peptides that are obtained from various natural sources such as many bacteria, fungi, plants, seaweeds, vertebrates, invertebrates and have been reported for various pharmacological properties such as anti-TB, anticancer, antimalarial, anti-inflammatory, anti-HIV, antibacterial, antifungal, and antidiabetic, activities. In view of the pharmacological significance of natural peptides, serious research efforts of many scientific groups and pharmaceutical companies have consequently focused on them to explore the possibility of developing their potential analogues as therapeutic agents. Solid phase and solution phase peptide synthesis are the two methodologies currently available for the synthesis of natural or synthetic linear or cyclic depsi-peptides. From a synthetic point of view, there is no doubt that the solid-phase methodology gained added advantages over solution phase methodology in terms of simplicity, purity of the compound and the speed with which peptides can be synthesised. In the present study total synthesis, purification and structural elucidation of analogues of natural anti-TB cyclic depsi-peptides such as depsidomycin, massetolides and viscosin has been attempted by solid phase method using standard Fmoc protocols and finally off resin cyclization in solution phase method. In case of depsidomycin, synthesis of linear peptide on solid phase could not be achieved because of two turn inducing amino acids in the peptide sequence, but total synthesis was achieved by convergent solid phase peptide synthesis followed by cyclization in solution phase method. The title compounds obtained were in good yields and characterized by NMR and HRMS. Anti-TB results revealed that the potential title compound exhibited promising activity at 4 µg/mL against H37Rv and 16 µg/mL against MDR strains of tuberculosis.

Keywords: total synthesis, cyclic depsi-peptides, anti-TB activity, tuberculosis

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519 The Utilization of Manganese-Enhanced Magnetic Resonance Imaging in the Fields of Ophthalmology and Visual Neuroscience

Authors: Parisa Mansour

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Understanding how vision works in both health and disease involves understanding the anatomy and physiology of the eye as well as the neural pathways involved in visual perception. The development of imaging techniques for the visual system is essential for understanding the neural foundation of visual function or impairment. MRI provides a way to examine neural circuit structure and function without invasive procedures, allowing for the detection of brain tissue abnormalities in real time. One of the advanced MRI methods is manganese-enhanced MRI (MEMRI), which utilizes active manganese contrast agents to enhance brain tissue signals in T1-weighted imaging, showcasing connectivity and activity levels. The way manganese ions build up in the eye, and visual pathways can be due to their spread throughout the body or by moving locally along axons in a forward direction and entering neurons through calcium channels that are voltage-gated. The paramagnetic manganese contrast is utilized in MRI for various applications in the visual system, such as imaging neurodevelopment and evaluating neurodegeneration, neuroplasticity, neuroprotection, and neuroregeneration. In this assessment, we outline four key areas of scientific research where MEMRI can play a crucial role - understanding brain structure, mapping nerve pathways, monitoring nerve cell function, and distinguishing between different types of glial cell activity. We discuss various studies that have utilized MEMRI to investigate the visual system, including delivery methods, spatiotemporal features, and biophysical analysis. Based on this literature, we have pinpointed key issues in the field related to toxicity, as well as sensitivity and specificity of manganese enhancement. We will also examine the drawbacks and other options to MEMRI that could offer new possibilities for future exploration.

Keywords: glial activity, manganese-enhanced magnetic resonance imaging, neuroarchitecture, neuronal activity, neuronal tract tracing, visual pathway, eye

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518 Efficiency of Information Technology Based Learning and Teaching in Higher Educations

Authors: Mahalingam Palaniandi

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Higher education plays vital role in the nation building process for a country and the rest of world. The higher education sector develops the change-agents for the various fields which will help the human-kind wheel to run further. Conventional and traditional class-room based learning and teaching was followed in many decades which is one-to-one and one-to-many. In a way, these are simplest form of learners to be assembled in a class room wherein the teacher used the blackboard to demonstrate the theory and laboratories used for practical. As the technology evolved tremendously for the last 40 years, the teaching and learning environment changed slowly, wherein, the learning community will be anywhere in the world and teacher deliver the content through internet based tools such as video conferencing, web based conferencing tools or E-learning platforms such as Blackboard or noodle. Present day, the mobile technologies plays an important tool to deliver the teaching content on-the-go. Both PC based and mobile based learning technology brought the learning and teaching community together in various aspects. However, as the learning technology also brought various hurdles for learning processes such as plagiarism and not using the reference books entirely as most of the students wants the information instantaneously using internet without actually going to the library to take the notes from the millions of the books which are not available online as e-books which result lack of fundamental knowledge of the concepts complex theories. However, technology is inseparable in human life, now-a-days and every part of it contains piece of information technology right from computers to home appliances. To make use of the IT based learning and teaching at most efficiency, we should have a proper framework and recommendations laid to the learning community in order to derive the maximum efficiency from the IT based teaching and leaning. This paper discusses various IT based tools available for the learning community, efficiency from its usage and recommendations for the suitable framework that needs to be implemented at higher education institutions which makes the learners stronger in both theory as well as real-time knowledge of their studies that is going to be used in their future for the better world.

Keywords: higher education, e-learning, teaching learning, eLearning tools

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517 Optimization of Acid Treatments by Assessing Diversion Strategies in Carbonate and Sandstone Formations

Authors: Ragi Poyyara, Vijaya Patnana, Mohammed Alam

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When acid is pumped into damaged reservoirs for damage removal/stimulation, distorted inflow of acid into the formation occurs caused by acid preferentially traveling into highly permeable regions over low permeable regions, or (in general) into the path of least resistance. This can lead to poor zonal coverage and hence warrants diversion to carry out an effective placement of acid. Diversion is desirably a reversible technique of temporarily reducing the permeability of high perm zones, thereby forcing the acid into lower perm zones. The uniqueness of each reservoir can pose several challenges to engineers attempting to devise optimum and effective diversion strategies. Diversion techniques include mechanical placement and/or chemical diversion of treatment fluids, further sub-classified into ball sealers, bridge plugs, packers, particulate diverters, viscous gels, crosslinked gels, relative permeability modifiers (RPMs), foams, and/or the use of placement techniques, such as coiled tubing (CT) and the maximum pressure difference and injection rate (MAPDIR) methodology. It is not always realized that the effectiveness of diverters greatly depends on reservoir properties, such as formation type, temperature, reservoir permeability, heterogeneity, and physical well characteristics (e.g., completion type, well deviation, length of treatment interval, multiple intervals, etc.). This paper reviews the mechanisms by which each variety of diverter functions and discusses the effect of various reservoir properties on the efficiency of diversion techniques. Guidelines are recommended to help enhance productivity from zones of interest by choosing the best methods of diversion while pumping an optimized amount of treatment fluid. The success of an overall acid treatment often depends on the effectiveness of the diverting agents.

Keywords: diversion, reservoir, zonal coverage, carbonate, sandstone

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516 Artificial Intelligence and Robotics in the Eye of Private Law with Special Regards to Intellectual Property and Liability Issues

Authors: Barna Arnold Keserű

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In the last few years (what is called by many scholars the big data era) artificial intelligence (hereinafter AI) get more and more attention from the public and from the different branches of sciences as well. What previously was a mere science-fiction, now starts to become reality. AI and robotics often walk hand in hand, what changes not only the business and industrial life, but also has a serious impact on the legal system. The main research of the author focuses on these impacts in the field of private law, with special regards to liability and intellectual property issues. Many questions arise in these areas connecting to AI and robotics, where the boundaries are not sufficiently clear, and different needs are articulated by the different stakeholders. Recognizing the urgent need of thinking the Committee on Legal Affairs of the European Parliament adopted a Motion for a European Parliament Resolution A8-0005/2017 (of January 27th, 2017) in order to take some recommendations to the Commission on civil law rules on robotics and AI. This document defines some crucial usage of AI and/or robotics, e.g. the field of autonomous vehicles, the human job replacement in the industry or smart applications and machines. It aims to give recommendations to the safe and beneficial use of AI and robotics. However – as the document says – there are no legal provisions that specifically apply to robotics or AI in IP law, but that existing legal regimes and doctrines can be readily applied to robotics, although some aspects appear to call for specific consideration, calls on the Commission to support a horizontal and technologically neutral approach to intellectual property applicable to the various sectors in which robotics could be employed. AI can generate some content what worth copyright protection, but the question came up: who is the author, and the owner of copyright? The AI itself can’t be deemed author because it would mean that it is legally equal with the human persons. But there is the programmer who created the basic code of the AI, or the undertaking who sells the AI as a product, or the user who gives the inputs to the AI in order to create something new. Or AI generated contents are so far from humans, that there isn’t any human author, so these contents belong to public domain. The same questions could be asked connecting to patents. The research aims to answer these questions within the current legal framework and tries to enlighten future possibilities to adapt these frames to the socio-economical needs. In this part, the proper license agreements in the multilevel-chain from the programmer to the end-user become very important, because AI is an intellectual property in itself what creates further intellectual property. This could collide with data-protection and property rules as well. The problems are similar in the field of liability. We can use different existing forms of liability in the case when AI or AI led robotics cause damages, but it is unsure that the result complies with economical and developmental interests.

Keywords: artificial intelligence, intellectual property, liability, robotics

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515 RNA-seq Analysis of Liver from NASH-HCC Model Mouse Treated with Streptozotocin-High Fat Diet

Authors: Bui Phuong Linh, Yuki Sakakibara, Ryuto Tanaka, Elizabeth H. Pigney, Taishi Hashiguchi

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Non-alcoholic steatohepatitis (NASH) is a chronic liver disease, often associated with type II diabetes, which sometimes progresses to more serious conditions such as liver fibrosis and hepatocellular carcinoma (HCC). NASH has become an important health problem worldwide, buttherapeutic agents for NASH have not yet been approved, and animal models with high clinical correlation are required. TheSTAM™ mouse shows the same pathological progression as human NASH patients and has been widely used for both drug efficacy and basic research, such as lipid profiling and gut microbiota research. In this study, we analyzed the RNA-seq data of STAM™mice at each pathological stage (steatosis, steatohepatitis, liver fibrosis, and HCC) and examined the clinical correlation at the genetic level. NASH was induced in male mice by a single subcutaneous injection of 200 µg streptozotocin solution 2 days after birth and feeding with high fat dietafter 4 weeks of age. The mice were sacrificed and livers collected at 6, 8, 10, 12, 16, and 20 weeks of age. For liver samples, the left lateral lobe was snap frozen in liquid nitrogen and stored at -80˚C for RNA-seq analysis. Total RNA of the cells was isolated using RNeasy mini kit. The gene expression of the canonical pathways in NASH progression from steatosis to hepatocellular carcinoma were analyzed, such as immune system process, oxidation-reduction process, lipid metabolic process. Moreover, since it has been reported that genetic traits are involved in the development of NASH-HCC, we next analyzed the genetic mutations in the STAM™mice. The number of individuals showing mutations in Mtorinvolved in Insulin signaling increases as the disease progresses, especially in the liver cancer phase. These results indicated a clinical correlation of gene profiles in the STAM™mouse.

Keywords: steatosis, non-alcoholic steatohepatitis, fibrosis, hepatocellular carcinoma, RNA-seq

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514 Sodium-glucose Co-transporter-2 Inhibitors in Heart Failure with Mildly Reduced Reduced Ejection Fraction: Future Perspectives in Patients with Neoplasia

Authors: M. A. Munteanu, A. M. Lungu, A. I. Chivescu, V. Teodorescu, E. Tufanoiu, C. Nicolae, T. I. Nanea

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Introduction: Sodium-glucose co-transporter 2 inhibitors (SGLT2i), which were first developed as antidiabetic medications, have demonstrated numerous positive benefits on the cardiovascular system, especially in the prevention of heart failure (HF). HF is a challenging, multifaceted disease that needs all-encompassing therapy. It should not be viewed as a limited form of heart illness but rather as a systemic disease that leads to multiple organ failure and death. SGLT2i is an extremely effective tool for treating HF by using its pleiotropic effects. In addition to its use in patients with diabetes mellitus who are at high cardiovascular risk or who have already experienced a cardiovascular event, SGLT2i administration has been shown to have positive effects on a variety of HF manifestations and stages, regardless of the patient's presence of diabetes mellitus. Material and Methods: According to the guide, 110 patients (83 males and 27 females) with heart failure with mildly reduced ejection fraction (HFmrEF), with T2D and neoplasia, were enrolled in the prospective study. The structural and functional state of the left ventricle myocardium and ejection fraction was assessed through echocardiography. Patients were randomized to receive once-daily dapagliflozin 10 mg. Results: Patients with HFmrEF were divided into 3 subgroups according to age. 7% (8) patients aged < 45 years, 35% (28) patients aged between 46-59 years, and 58% (74) patients aged> 60 years. The most prevalent comorbidities were hypertension (43.1%), coronary heart disease (40%), and obesity (33.2%). Study drug discontinuation and serious adverse events were not frequent in the subgroups, in either men or women, until now. Conclusions: SGLT-2 inhibitors are a novel class of antidiabetic agents that have demonstrated positive efficacy and safety outcomes in the setting of HFmrEF. Until now, in our study, dapagliflozin was safe and well-tolerated irrespective of sex.

Keywords: diabetes mellitus type 2, Sodium-glucose co-transporters-2 inhibitors, heart failure, neoplasia

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513 Urban Agriculture among Households of Makurdi Metropolis of Benue State, Nigeria: Key Challenges

Authors: Evangeline Mbah, Margret Okeke, Agbo Joseph

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Agriculture was primarily a rural activity in Nigeria, but due to increasing demand for food and jobs for many urban dwellers, it became necessary for urban households to embark on farming as a means of improving household food security and additional income for economic empowerment. Urban agriculture serves as a veritable tool for poverty reduction among people living in urban areas mostly low-income earners and unemployed. The survey was conducted to identify key challenges encountered by households in Makurdi metropolis of Benue state, Nigeria who are engaged in urban agriculture. A well-structured questionnaire was used to collect data from a sample of respondents used for the study. Data were analyzed using frequency, percentage, mean score and standard deviation. Results show that a greater percentage (46.0%) of the respondents engaged in cultivation of leafy vegetable, 22.0% cultivated cassava, 21.0% planted sweet potato, 18.0% cultivated tomato while 56.0% reared poultry, 23.0% kept goat, among others. Sources of agricultural information indicated by the respondents were family members/relations (85.0%), friends/neighbours (73.0%), radio (68.0%), extension agents (57.0%), etc. Major challenges encountered by the respondents in urban agriculture include inadequate size of farmland (M= 2.72), lack of access to credit facilities (M= 2.63), lack of funds (M= 2.50), high cost of labour (M= 2.49), insecurity of lands (M= 2.46), theft of crops at maturity (M= 2.38), lack of farm inputs such as improved varieties of seeds, fertilizer and exotic breeds of livestock (M= 2.23), destruction of crops by stray farm animals (M= 1.96), among others. The study recommends that there is a need for adequate provision of farm inputs by the government at all levels at a subsidized rate in order to reduce the cost of production and enhance optimum productivity.

Keywords: urban, agriculture, household, challenges, Makurdi, Nigeria

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512 Producing and Mechanical Testing of Urea-Formaldehyde Resin Foams Reinforced by Waste Phosphogypsum

Authors: Krasimira Georgieva, Yordan Denev

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Many of thermosetting resins have application only in filled state, reinforced with different mineral fillers. The co-filling of polymers with mineral filler and gases creates a possibility for production of polymer composites materials with low density. This processing leads to forming of new materials – gas-filled plastics (polymer foams). The properties of these materials are determined mainly by the shape and size of internal structural elements (pores). The interactions on the phase boundaries have influence on the materials properties too. In the present work, the gas-filled urea-formaldehyde resins were reinforced by waste phosphogypsum. The waste phosphogypsum (CaSO4.2H2O) is a solid by-product in wet phosphoric acid production processes. The values of the interactions polymer-filler were increased by using two modifying agents: polyvinyl acetate for polymer matrix and sodium metasilicate for filler. Technological methods for gas-filling and recipes of urea-formaldehyde based materials with apparent density 20-120 kg/m3 were developed. The heat conductivity of the samples is between 0.024 and 0.029 W/moK. Tensile analyses were carried out at 10 and 50% deformation and show values 0.01-0.14 MPa and 0.01-0.09 MPa, respectively. The apparent density of obtained materials is between 20 and 92 kg/m3. The changes in the tensile properties and density of these materials according to sodium metasilicate content were studied too. The mechanism of phosphogypsum adsorption modification was studied using methods of FT-IR spectroscopy. The structure of the gas-filled urea-formaldehyde resins was described by results of electron scanning microscopy at three different magnification ratios – x50, x150 and x 500. The aim of present work is to study the possibility of the usage of phosphogypsum as mineral filler for urea-formaldehyde resins and development of a technology for the production of gas-filled reinforced polymer composite materials. The structure and the properties of obtained composite materials are suitable for thermal and sound insulation applications.

Keywords: urea formaldehyde resins, gas-filled thermostes, phosphogypsum, mechanical properties

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511 Risk in the South African Sectional Title Industry: An Assurance Perspective

Authors: Leandi Steenkamp

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The sectional title industry has been a part of the property landscape in South Africa for almost half a century, and plays a significant role in addressing the housing problem in the country. Stakeholders such as owners and investors in sectional title property are in most cases not directly involved in the management thereof, and place reliance on the audited annual financial statements of bodies corporate for decision-making purposes. Although the industry seems to be highly regulated, the legislation regarding accounting and auditing of sectional title is vague and ambiguous. Furthermore, there are no industry-specific auditing and accounting standards to guide accounting and auditing practitioners in performing their work and industry financial benchmarks are not readily available. In addition, financial pressure on sectional title schemes is often very high due to the fact that some owners exercise unrealistic pressure to keep monthly levies as low as possible. All these factors have an impact on the business risk as well as audit risk of bodies corporate. Very little academic research has been undertaken on the sectional title industry in South Africa from an accounting and auditing perspective. The aim of this paper is threefold: Firstly, to discuss the findings of a literature review on uncertainties, ambiguity and confusing aspects in current legislation regarding the audit of a sectional title property that may cause or increase audit and business risk. Secondly, empirical findings of risk-related aspects from the results of interviews with three groups of body corporate role-players will be discussed. The role-players were body corporate trustee chairpersons, body corporate managing agents and accounting and auditing practitioners of bodies corporate. Specific reference will be made to business risk and audit risk. Thirdly, practical recommendations will be made on possibilities of closing the audit expectation gap, and further research opportunities in this regard will be discussed.

Keywords: assurance, audit, audit risk, body corporate, corporate governance, sectional title

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510 Development of Carrageenan-Psyllium/Montmorillonite Clay Hybrid Hydrogels for Agriculture Purpose

Authors: D. Aydinoglu, N. Karaca, O. Ceylan

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Limited water resources on the earth come first among the most alarming issues. In this respect, several solutions from treatment of waste water to water management have been proposed. Recently, use of hydrogels as soil additive, which is one of the water management ways in agriculture, has gained increasing interest. In traditional agriculture applications, water used with irrigation aim, rapidly flows down between the pore structures in soil, without enough useful for soil. To overcome this fact and increase the abovementioned limit values, recently, several natural based hydrogels have been suggested and tested to find out their efficiency in soil. However, most of these researches have dealt with grafting of synthetic acrylate based monomers on natural gelling agents, most probably due to reinforced of the natural gels. These results motivated us to search a natural based hydrogel formulations, not including any synthetic component, and strengthened with montmorillonite clay instead of any grafting polymerization with synthetic monomer and examine their potential in this field, as well as characterize of them. With this purpose, carrageenan-psyllium/ montmorillonite hybrid hydrogels have been successively prepared. Their swelling capacities were determined both in deionized and tap water and were found to be dependent on the carrageenan, psyllium and montmorillonite ratios, as well as the water type. On the other hand, mechanical tests revealed that especially carrageenan and montmorillonite contents have a great effect on gel strength, which is one of the essential features, preventing the gels from cracking resulted in readily outflow of all the water in the gel without beneficial for soil. They found to reach 0.23 MPa. The experiments carried out with soil indicated that hydrogels significantly improved the water uptake capacities and water retention degrees of the soil from 49 g to 85 g per g of soil and from 32 to 67%, respectively, depending on the ingredient ratios. Also, biodegradation tests demonstrated that all the hydrogels undergo biodegradation, as expected from their natural origin. The overall results suggested that these hybrid hydrogels have a potential for use as soil additive and can be safely used owing to their totally natural structure.

Keywords: carrageenan, hydrogel, montmorillonite, psyllium

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509 Histological and Microbiological Study about the Pneumonic Lungs of Calves Slaughtered in the Slaughterhouse of Batna

Authors: Hamza Hadj Abdallah, Brahim Belabdi

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Respiratory disease is a dominant pathology in cattle. It causes mortality and especially morbidity and irreversible damage. Although the dairy herd is affected, it is essentially the lactating herd and especially young cattle either nursing or fattening that undergo the greatest economic impact. The objective of this study is to establish a microbiological diagnosis of bovine respiratory inffections from lung presented with gross lesions at the slaughter of Batna. A total of 124 samples (pharyngeal and nasal swabs and lung fragments) from 31 seven months old calves, with lung lesions was collected to determine possible correlations between etiologic agents and lesion types. The hépatisation injury (or consolidation) was the major lesion (45.17%) preferentially localized in the right apical lobe. A diverse microbial flora (15 genera and 291 strains was isolated. The bacteria most frequently isolated are the Enterobacteriaceae (49.45%), Staphylococci (25.1%) followed by non Enterobacteriaceae bacilli represented by Pseudomonas (5.83%) and finally, Streptococcus (13.38 %). The pneumotropic bacteria (Pasteurellaaerogenes and Pasteurellapneumotropica) were isolated at a rate of 0.68%. The study of the sensitivity of some germs to antibiotics showed a sensitivity of 100% for ceftazidime. A very high sensitivity was also observed for kanamycin, Ciprofloxacin, Imepinem, Cefepime, Tobramycin and Gentamycin (between 90% and 97%). Strains of E. coli showed a sensitivity of 100% for Imepinem, while only 55.9% of the strains were sensitive to Ampicillin. The isolated Pasteurella exhibited excellent sensitivity (100%) for the antimicrobials used with the exception of Colistin and Ticarcillin-Clavulanic acid association which showed a sensitivity of 50%.This survey has demonstrated the strong spread of atypical pneumonia in cattle population (bulls) at the slaughterhouse of Batna justifying stunting and losses in cattle farms in the region.Thus, it was considered urgent to establish a profile of sensitivity of different germs to antibiotics isolated to limit this increasingly dreadful infection.

Keywords: Pasteurella, enterobacteria, bacteriology, pneumonia

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508 Composite Materials from Epoxidized Linseed Oil and Lignin

Authors: R. S. Komartin, B. Balanuca, R. Stan

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the last decades, studies about the use of polymeric materials of plant origin, considering environmental concerns, have captured the interest of researchers because these represent an alternative to petroleum-derived materials. Vegetable oils are one of the preferred alternatives for petroleum-based raw materials having long aliphatic chains similar to hydrocarbons which means that can be processed using conventional chemistry. Epoxidized vegetable oils (EVO) are among the most interesting products derived from oil both for their high reactivity (epoxy group) and for the potential to react with compounds from various classes. As in the case of epoxy resins starting from petrochemical raw materials, those obtained from EVO can be crosslinked with different agents to build polymeric networks and can also be reinforced with various additives to improve their thermal and mechanical performances. Among the multitude of known EVO, the most common in industrial practice are epoxidized linseed oils (ELO) and epoxidized soybean oils (ESO), the first with an iodine index over 180, the second having a lower iodine index but being cheaper. On the other hand, lignin (Ln) is the second natural organic material as a spread, whose use has long been hampered because of the high costs associated with its isolation and purification. In this context, our goal was to obtain new composite materials with satisfactory intermediate properties in terms of stiffness and elasticity using the characteristics of ELO and Ln and choosing the proper curing procedure. In the present study linseed oil (LO) epoxidation was performed using peracetic acid generated in situ. The obtained bio-based epoxy resin derived from linseed oil was used further to produce the new composites byloading Ln in various mass ratios. The resulted ELO-Ln blends were subjected to a dual-curing protocol, namely photochemical and thermal. The new ELO-Ln composites were investigated by FTIR spectrometry, thermal stability, water affinity, and morphology. The positive effect of lignin regarding the thermal stability of the composites could be proved. The results highlight again the still largely unexplored potential of lignin in industrial applications.

Keywords: composite materials, dual curing, epoxidized linseed oil, lignin

Procedia PDF Downloads 156
507 Hydrodynamic Analysis of Payload Bay Berthing of an Underwater Vehicle With Vertically Actuated Thrusters

Authors: Zachary Cooper-Baldock, Paulo E. Santos, Russell S. A. Brinkworth, Karl Sammut

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- In recent years, large unmanned underwater vehicles such as the Boeing Voyager and Anduril Ghost Shark have been developed. These vessels can be structured to contain onboard internal payload bays. These payload bays can serve a variety of purposes – including the launch and recovery (LAR) of smaller underwater vehicles. The LAR of smaller vessels is extremely important, as it enables transportation over greater distances, increased time on station, data transmission and operational safety. The larger vessel and its payload bay structure complicate the LAR of UUVs in contrast to static docks that are affixed to the seafloor, as they actively impact the local flow field. These flow field impacts require analysis to determine if UUV vessels can be safely launched and recovered inside the motherships. This research seeks to determine the hydrodynamic forces exerted on a vertically over-actuated, small, unmanned underwater vehicle (OUUV) during an internal LAR manoeuvre and compare this to an under-actuated vessel (UUUV). In this manoeuvre, the OUUV is navigated through the stern wake region of the larger vessel to a set point within the internal payload bay. The manoeuvre is simulated using ANSYS Fluent computational fluid dynamics models, covering the entire recovery of the OUUV and UUUV. The analysis of the OUUV is compared against the UUUV to determine the differences in the exerted forces. Of particular interest are the drag, pressure, turbulence and flow field effects exerted as the OUUV is driven inside the payload bay of the larger vessel. The hydrodynamic forces and flow field disturbances are used to determine the feasibility of making such an approach. From the simulations, it was determined that there was no significant detrimental physical forces, particularly with regard to turbulence. The flow field effects exerted by the OUUV are significant. The vertical thrusters exert significant wake structures, but their orientation ensures the wake effects are exerted below the UUV, minimising the impact. It was also seen that OUUV experiences higher drag forces compared to the UUUV, which will correlate to an increased energy expenditure. This investigation found no key indicators that recovery via a mothership payload bay was not feasible. The turbulence, drag and pressure phenomenon were of a similar magnitude to existing static and towed dock structures.

Keywords: underwater vehicles, submarine, autonomous underwater vehicles, auv, computational fluid dynamics, flow fields, pressure, turbulence, drag

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506 The Impact of Oxytetracycline on the Aquaponic System, Biofilter, and Plants

Authors: Hassan Alhoujeiri, Angele Matrat, Sandra Beaufort, Claire joaniss Cassan, Jerome Silvester

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Aquaponics is a sustainable food production technology, and its transition to industrial-scale systems has created several challenges that require further investigation in order to make it a robust process. One of the critical concerns is the potential accumulation of compounds from veterinary treatments, phytosanitary agents, fish feed, or simply from contaminated water sources. The accumulation of these substances could negatively impact fish health, microbial biofilters, and plant growth, thereby disrupting the system’s overall balance and functionality. The lack of legislation and knowledge regarding the presence of such compounds in aquaponic systems raises concerns about their potential impact on both system balance and food safety. In this study, we focused on the effects of oxytetracycline (OTC), an antibiotic commonly used in aquaculture, on both the microbial biofilter and plant growth. Although OTC is rarely applied in aquaponics today, the fish compartment may need to be isolated from the system during treatment, as it inhibits specific bacterial populations, which could affect the microbial biofilter's efficiency. However, questions remain about the aquaponic system's tolerance threshold, particularly in cases of treatment or residual OTC traces post-treatment. This study results indicated a decline in microbial biofilter activity to 20% compared to the control, potentially corresponding to treatments of 41 mg/L of OTC. Analysis of microbial populations in the biofilter, using flow cytometry and microscopy (confocal and scanning electron microscopy), revealed an increase in bacterial mortality without disrupting the microbial biofilm. Additionally, OTC exposure led to noticeable changes in plant morphology (e.g., color) and growth, though it did not fully inhibit development. However, no significant effects were observed on seed germination at the tested concentrations despite a measurable impact on subsequent plant growth.

Keywords: aquaponic, oxytetracycline, nitrifying biofilter, plant, micropollutants, sustainability

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505 Molecular Detection of Helicobacter Pylori and Its Association with TNFα-308 Polymorphism in Cardiovascular Diseases

Authors: Azar Sharafianpor, Hossein Rassi, Fahimeh Nemati Mansur

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Cardiovascular diseases (CVD) are the most important cause of death in industrialized and developing countries such as Iran. The most important risk factors for the CVD, genetic factors and chronic infectious agents, such as Helicobacter pylori, can be mentioned. The TNFα gene is one of the most important anti-inflammatory cytokines that can affect the sensitivity, efficacy, and ability of the immune response to chronic infections. Some TNF-α gene polymorphisms, including the replacement of the G nucleotide G with A at position 308 in the promoter region of TNF-α, increase the transcription of cytokines in the target cells and thus predispose a person to chronic infections. This study examines the TNF-α 308 polymorphism and its association with Helicobacter pylori infection in this disease. This study was a case-control study in which 154 patients were examined as cases or patients with symptoms of myocardial infarction or angina and 160 as controls or healthy subjects. All of the subjects at different ages were given venous blood and age, BMI, cholesterol, LDL, and HDL were determined. DNA was extracted from the specimens, and the cagA gene from H. pylori and the TNF-α-308 polymorphism were determined by PCR in patients and healthy subjects. Statistical analysis was performed with Epi Info software. The results showed that the frequency of H. pylori infection in the patients and healthy group were 53.23% (82 out of 154) and 47.5% (76 out of 160). There was no significant difference in H. pylori outbreak between the two groups. The frequencies of TNF-α-308 genotype for GG, GA, and AA in patients were 0.17, 0.49, and 0.34, respectively, whereas for controls 0.47, 0.35, and 0.18 for GG, GA, and AA, respectively. The frequency of genotype analysis of TNF-α-308 polymorphisms in both patients and healthy groups showed that there was a significant difference in the frequency of genotypes and the AA genotype was higher in the affected individuals. Also, there was a significant relationship between the genotype and the contamination with H. pylori and changes in cholesterol, LDL, and HDL levels were observed. The results of the study indicate that H. pylori detection in individuals with AA genotype in people under 50 years of age can play an important role in early diagnosis and treatment of cardiovascular disease.

Keywords: Helicobacter pylori, TNFα gene, cardiovascular diseases, TNFα-308 polymorphism

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504 Passenger Preferences on Airline Check-In Methods: Traditional Counter Check-In Versus Common-Use Self-Service Kiosk

Authors: Cruz Queen Allysa Rose, Bautista Joymeeh Anne, Lantoria Kaye, Barretto Katya Louise

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The study presents the preferences of passengers on the quality of service provided by the two airline check-in methods currently present in airports-traditional counter check-in and common-use self-service kiosks. Since a study has shown that airlines perceive self-service kiosks alone are sufficient enough to ensure adequate services and customer satisfaction, and in contrast, agents and passengers stated that it alone is not enough and that human interaction is essential. In reference with former studies that established opposing ideas about the choice of the more favorable airline check-in method to employ, it is the purpose of this study to present a recommendation that shall somehow fill-in the gap between the conflicting ideas by means of comparing the perceived quality of service through the RATER model. Furthermore, this study discusses the major competencies present in each method which are supported by the theories–FIRO Theory of Needs upholding the importance of inclusion, control and affection, and the Queueing Theory which points out the discipline of passengers and the length of the queue line as important factors affecting quality service. The findings of the study were based on the data gathered by the researchers from selected Thomasian third year and fourth year college students currently enrolled in the first semester of the academic year 2014-2015, who have already experienced both airline check-in methods through the implication of a stratified probability sampling. The statistical treatments applied in order to interpret the data were mean, frequency, standard deviation, t-test, logistic regression and chi-square test. The final point of the study revealed that there is a greater effect in passenger preference concerning the satisfaction experienced in common-use self-service kiosks in comparison with the application of the traditional counter check-in.

Keywords: traditional counter check-in, common-use self-service Kiosks, airline check-in methods

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503 Antibacterial Effects of Garcinia mangostana on Canine Superficial Pyoderma Pathogen, Staphylococcus pseudintermedius

Authors: Sineenat Kempubpha, Phornpa-Ngan Muadmuang, Putthamas Phetmuangprab, Surin Promphet, Sopita Bandit

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Introduction: Discarded pericarp of mangosteen (Garcinia mangostana) is a benefit to be developed as veterinary phytopharmacal products since it made up of abundance pharmacological active compounds. The active compounds of mangosteen pericarp not only act as an antihistamine, an anti-inflammatory, heart disease and HIV therapeutic substances but also act as antibacterial and antifungal agents. Aim: This study was an in vitro procedural attempt to determine the antibacterial effects of mangosteen pericarp 95% ethanol extract on the main causative pathogen of canine superficial pyoderma, Staphylococcus pseudintermedius. Methods: S. pseudintermedius were collected from various sites of the skin of canine superficial pyoderma dogs and were revived and lawn cultured. The S. pseudintermedius growth inhibition study was determined by disc diffusion technique, the mangosteen pericarp crude extracted was dissolved in 3 types of solvents (95% ethanol, 2% DMSO and distilled water, respectively). The micro broth dilution technique was used for determining both minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values. Statistical analysis was done by calculating the mean of the zones of inhibition of tested microorganisms. Results: S. pseudintermedius growth inhibition study showed that the inhibition efficacy of 95% ethanol was greater than the inhibition efficacy of 2% DMSO and distilled water (9.10±0.18 mm, 6.95±0.60 mm and 6.80±0.18 mm, respectively). The MIC value was 125 µg/ml and the MBC value was 1 mg/ml. Conclusion: Mangosteen pericarp extract dissolved with 95% ethanol showed the highest zone of inhibition against the tested microorganisms. The MIC value was 125 µg/ml and the MBC value was 1 mg/ml which suggests its potent antibacterial action against S. pseudintermedius. However, further analytical studies are needed to isolate the key molecules of mangosteen pericarp for higher effect on canine superficial pyoderma microorganism therapeutic products.

Keywords: mangosteen, Garcinia mangostana, Staphylococcus pseudintermedius, canine superficial pyoderma, in vitro study

Procedia PDF Downloads 280
502 Dimensionality Reduction in Modal Analysis for Structural Health Monitoring

Authors: Elia Favarelli, Enrico Testi, Andrea Giorgetti

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Autonomous structural health monitoring (SHM) of many structures and bridges became a topic of paramount importance for maintenance purposes and safety reasons. This paper proposes a set of machine learning (ML) tools to perform automatic feature selection and detection of anomalies in a bridge from vibrational data and compare different feature extraction schemes to increase the accuracy and reduce the amount of data collected. As a case study, the Z-24 bridge is considered because of the extensive database of accelerometric data in both standard and damaged conditions. The proposed framework starts from the first four fundamental frequencies extracted through operational modal analysis (OMA) and clustering, followed by density-based time-domain filtering (tracking). The fundamental frequencies extracted are then fed to a dimensionality reduction block implemented through two different approaches: feature selection (intelligent multiplexer) that tries to estimate the most reliable frequencies based on the evaluation of some statistical features (i.e., mean value, variance, kurtosis), and feature extraction (auto-associative neural network (ANN)) that combine the fundamental frequencies to extract new damage sensitive features in a low dimensional feature space. Finally, one class classifier (OCC) algorithms perform anomaly detection, trained with standard condition points, and tested with normal and anomaly ones. In particular, a new anomaly detector strategy is proposed, namely one class classifier neural network two (OCCNN2), which exploit the classification capability of standard classifiers in an anomaly detection problem, finding the standard class (the boundary of the features space in normal operating conditions) through a two-step approach: coarse and fine boundary estimation. The coarse estimation uses classics OCC techniques, while the fine estimation is performed through a feedforward neural network (NN) trained that exploits the boundaries estimated in the coarse step. The detection algorithms vare then compared with known methods based on principal component analysis (PCA), kernel principal component analysis (KPCA), and auto-associative neural network (ANN). In many cases, the proposed solution increases the performance with respect to the standard OCC algorithms in terms of F1 score and accuracy. In particular, by evaluating the correct features, the anomaly can be detected with accuracy and an F1 score greater than 96% with the proposed method.

Keywords: anomaly detection, frequencies selection, modal analysis, neural network, sensor network, structural health monitoring, vibration measurement

Procedia PDF Downloads 123
501 A Study on the Prevalence and Microbiological Profile of Nosocomial Infections in the ICU of a Tertiary Care Hospital in Eastern India

Authors: Pampita Chakraborty, Sukumar Mukherjee

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This study was done to determine the prevalence of nosocomial infections in the ICU and to identify the common microorganisms causing these infections and their antimicrobial sensitivity pattern. Nosocomial infection or hospital-acquired infection is a localized or a systemic condition resulting from an adverse reaction to the presence of infectious agents. Nosocomial infections are not present or incubating when the patient is admitted to hospital or other health care facility. They are caused by pathogens that easily spread through the body. Many hospitalized patients have compromised immune systems, so they are less able to fight off infections. These infections occur worldwide, both in the developed and developing the world. They are a significant burden to patients and public health. They are a major cause of death and increased morbidity in hospitalized patients, which is a matter of serious concern today. This study was done during the period of one year (2012-2013) in the ICU of the tertiary care hospital in eastern India. Prevalence of nosocomial infection was determined; site of infection and the pattern of microorganisms were identified along with the assessment of antibiotic susceptibility profile. Patients who developed an infection after 48 hours of admission to the ICU were included in the study. A total of 324 ICU patients were analyzed, of these 79 patients were found to have developed a nosocomial infection (24.3% prevalence). Urinary tract infection was found to be more predominant followed by respiratory tract infection and soft tissue infection. The most frequently isolated microorganism was E. coli, Pseudomonas aeruginosa, Klebsiella pneumoniae followed by other organisms respectively. Antibiotic susceptibility test of these isolates was done against commonly used antibiotics. Patients admitted to the ICU are especially susceptible to nosocomial infections. Despite adequate antimicrobial treatment, nosocomial ICU infections can significantly affect ICU stay and can cause an increase in patient’s morbidity and mortality. Adherence to infection protocol, proper monitoring and the judicious use of antibiotics are important in preventing such infections on a regular basis.

Keywords: antibiotic susceptibility, intensive care unit, nosocomial infection, nosocomial pathogen

Procedia PDF Downloads 323
500 Marketing Strategy and Marketing Mix for Rural Tour Package in Bali: Case Study of Munduk

Authors: Made Darmiati, Ni Putu Evi Wijayanti, Ni Ketut Wiwiek Agustina, Putu Gde Arie Yudhistira, Marcel Hardono

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The establishment of tourist village has been the main concern for pro-poor tourism in Indonesia especially in Bali in order to create alternative tourist destination. The case study of this research was Munduk, a tourist village located in Buleleng Regency, Bali Province. Munduk has been unstable in terms of tourist visit in 2012 until 2016. The concept of marketing strategy and its marketing mix are concepts that suitable for application in Munduk as the prime owner of trekking and other rural tour packages to increase the number of visitor in particularly during low season. The research study aims to determine the internal factors (strengths and weaknesses) and external factors (opportunities and threats) impacting the number of tourist visit so that they could formulate appropriate marketing strategy for Munduk Tourist Village. Data has been obtained by observation, interviews with stakeholders, questionnaire to 100 participants and documentation. In addition, this research study uses descriptive qualitative methods and techniques known as SWOT (Strengths, Weaknesses, Opportunities, Threats) analysis by internal factors and external factors impacting the level of tourist visit to Munduk Tourist Village in Buleleng Regency, Bali. The sampling was done by ‘accidental sampling technique’ to obtain the participants to analyse the results of the SWOT analysis. Further assessment of internal and external weights has resulted respectively (1.84 , 1.84) which are in the first quadrant of the diagram in which S-O (Strengths-Opportunities) Strategy. As the prime owner of the trekking and other rural tour packages in the village, Munduk should maximise its strengths and take other opportunities as possible to wrap and design trekking and other rural tour packages and then offer the package to travel agents in Bali.

Keywords: marketing mix, marketing strategy, rural tourism, SWOT matrix

Procedia PDF Downloads 277
499 Angiogenic Potential of Collagen Based Biomaterials Implanted on Chick Embryo Chorioallantoic Membrane as Alternative Microenvironment for in Vitro and in Vivo Angiogenesis Assays

Authors: Anca Maria Cimpean, Serban Comsa

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Chick embryo chorioallantoic membrane (CAM) is a well vascularised in vivo experimental model used as a platform for testing the behavior of different implants inserted on it from tumor fragments to therapeutic agents or various biomaterials. Five types of collagen-based biomaterials with 2D and 3D structure (MotifMesh, Optimaix2D, Optimaix3D, Dual Layer Collagen and Xenoderm) were implanted on CAM and continuously evaluated by stereomicroscope for up to 5 days post-implant with an emphasis of their ability to requisite and develop new blood vessels (BVs) followed by microscopic analysis. MotifMEsh did not induce any angiogenic response lacking to be invaded by BVs from the CAM, but it induced intense inflammatory response necrosis and fibroblastic reaction around the implant. Optimaix2D has good adherence. CAM with minimal or no inflammatory reaction, a good integration of the CAM between the collagen mesh’s fibers, consistent adhesion of the cells to the collagen fibers,and a good ability to form pseudo-vascular channels filled with cells. Optimaix3D induced the highest angiogenic effects on CAM. The material shows good integration on CAM. The collagen fibers of the material show the ability to organize themselves into linear and tubular structures. It is possible to see blood elements, especially at the periphery of the implant. Dual-layer collagen behaves similar to Optimaix 3D, while Xenoderm induced a moderate angiogenic effect on CAM. Based on these data, we may conclude that collagen-based materials have variable ability to requisite and develop new blood vessels. A proper selection of collagen-based biomaterial scaffolds may crucially influence the acquisition and development of blood vessels during angiogenesis assays.

Keywords: chick embryo chorioallantoic membrane, collagen scaffolds, blood vessels, vascular microenvironment

Procedia PDF Downloads 193
498 Ultrasonic Agglomeration of Protein Matrices and Its Effect on Thermophysical, Macro- and Microstructural Properties

Authors: Daniela Rivera-Tobar Mario Perez-Won, Roberto Lemus-Mondaca, Gipsy Tabilo-Munizaga

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Different dietary trends worldwide seek to consume foods with anti-inflammatory properties, rich in antioxidants, proteins, and unsaturated fatty acids that lead to better metabolic, intestinal, mental, and cardiac health. In this sense, food matrices with high protein content based on macro and microalgae are an excellent alternative to meet the new needs of consumers. An emerging and environmentally friendly technology for producing protein matrices is ultrasonic agglomeration. It consists of the formation of permanent bonds between particles, improving the agglomeration of the matrix compared to conventionally agglomerated products (compression). Among the advantages of this process are the reduction of nutrient loss and the avoidance of binding agents. The objective of this research was to optimize the ultrasonic agglomeration process in matrices composed of Spirulina (Arthrospira platensis) powder and Cochayuyo (Durvillae Antartica) flour, by means of the response variable (Young's modulus) and the independent variables were the process conditions (percentage of ultrasonic amplitude: 70, 80 and 90; ultrasonic agglomeration times and cycles: 20, 25 and 30 seconds, and 3, 4 and 5). It was evaluated using a central composite design and analyzed using response surface methodology. In addition, the effects of agglomeration on thermophysical and microstructural properties were evaluated. It was determined that ultrasonic compression with 80 and 90% amplitude caused conformational changes according to Fourier infrared spectroscopy (FTIR) analysis, the best condition with respect to observed microstructure images (SEM) and differential scanning calorimetry (DSC) analysis, was the condition of 90% amplitude 25 and 30 seconds with 3 and 4 cycles of ultrasound. In conclusion, the agglomerated matrices present good macro and microstructural properties which would allow the design of food systems with better nutritional and functional properties.

Keywords: ultrasonic agglomeration, physical properties of food, protein matrices, macro and microalgae

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497 Preclinical Studying of Stable Fe-Citrate Effect on 68Ga-Citrate Tissue Distribution

Authors: A. S. Lunev, A. A. Larenkov, O. E. Klementyeva, G. E. Kodina

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Background and aims: 68Ga-citrate is one of prospective radiopharmaceutical for PET-imaging of inflammation and infection. 68Ga-citrate is 67Ga-citrate analogue using since 1970s for SPECT-imaging. There's known rebinding reaction occurs past Ga-citrate injection and gallium (similar iron Fe3+) binds with blood transferrin. Then radiolabeled protein complex is delivered to pathological foci (inflammation/infection sites). But excessive gallium bindings with transferrin are cause of slow blood clearance, long accumulation time in foci (24-72 h) and exception of application possibility of the short-lived gallium-68 (T½ = 68 min). Injection of additional chemical agents (e.g. Fe3+ compounds) competing with radioactive gallium to the blood transferrin joining (blocking of its metal binding capacity) is one of the ways to solve formulated problem. This phenomenon can be used for correction of 68Ga-citrate pharmacokinetics for increasing of the blood clearance and accumulation in foci. The aim of real studying is research of effect of stable Fe-citrate on 68Ga-citrate tissue distribution. Materials and methods: 68Ga-citrate without/with extra injection of stable Fe-citrate (III) was injected nonlinear mice with inflammation models (aseptic soft tissue inflammation, lung infection, osteomyelitis). PET/X-RAY Genisys4 (Sofie Bioscience, USA) was used for non-invasive PET imaging (for 30, 60, 120 min past injection 68Ga-citrate) with subsequent reconstruction of imaging and their analysis (value of clearance, distribution volume). Scanning time is 10 min. Results and conclusions: I. v. injection of stable Fe-citrate blocks the metal-binding capability of transferrin serum and allows decreasing gallium-68 radioactivity in blood significantly and increasing accumulation in inflammation (3-5 time). It allows receiving more informative PET-images of inflammation early (for 30-60 min after injection). Pharmacokinetic parameters prove it. Noted there is no statistically significant difference between 68Ga-citrate accumulation for different inflammation model because PET imaging is indication of pathological processes and is not their identification.

Keywords: 68Ga-citrate, Fe-citrate, PET imaging, mice, inflammation, infection

Procedia PDF Downloads 488
496 New Insights Into Gluten-Free Bread Staling Treatment

Authors: Sayed Mostafa, Siham Mostafa Mohamed Faheid, Ibrahim Rizk Sayed Ahmed, Yasser Fehry Mohamed Kishk, Gamal Hassan Ragab

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Gluten-free foods are still the only treatment for gluten-allergic patients. Consequently, this study is concerned with improving the quality attributes of gluten-free bread using different concentrations (0, 20, 40, 60 and 80ppm) of all maltogenic α-amylase (MA) and xylanase (XY) compared with wheat flour Balady bread and untreated gluten-free Balady bread (GFBB). Pasting properties, falling number, water activity, alkaline water retention capacity (AWRC) and sensory properties (fresh bread, after 24h, after 48h and after 72h) of gluten-free bread were evaluated. Additionally, the effect of merging different concentrations of maltogenic α-amylase and xylanase on stalling behavior (AWRC) and sensory properties of gluten-free Balady bread was investigated. The addition of MA led to a gradually decreased peak viscosity, breakdown, setback and pasting temperature of GFBB with the increasing level of MA. Maltogenic α-amylase and xylanase addition led to a reduction in the FN values compared to the untreated gluten-free sample, noting that the MA-treated samples showed a significant decrease compared to the XY-treated and untreated samples. Wheat flour Balady bread significantly showed a higher value of AWRC compared to untreated gluten-free Balady bread at different storage periods (zero time, after 24h, after 48h and after 72h). MA-treated samples showed higher water binding capacity and water activity (aw)in comparison with XY-treated samples, with significance during all storage periods. Concerning the overall acceptability during the third day, the highest score (4.6) was observed by the GFBB sample containing 40ppm MA, followed by 4.3, which was investigated by the GFBB sample containing 80ppm XY with no significance between them and with significance compared to the other samples.

Keywords: celiac disease, gluten-free products, anti-stalling agents, maltogenic α-amylase, xylanase

Procedia PDF Downloads 85
495 Sensory Evaluation and Microbiological Properties of Gouda Cheese Affected by Bunium persicum (Boiss.) Essential Oil

Authors: N. Noori, P. Taherkhani, A. Akhondzadeh Basti, H. Gandomi, M. Alimohammadi

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Research on natural antimicrobial agents, especially of plant origin, highly noticed in recent years and evaluation of antimicrobial effects of native plants such as Bunium persicum Boiss. is especially important. In the present study, sensory characteristics and microbiological properties of Gouda cheese affected by different concentrations of Bunium persicum Boiss. essential oil were investigated. Extraction of the essential oil was performed by hydro distillation. The oil was analyzed by GC using flame ionization (FID) and GC/ MS for detection. The antimicrobial effects were determined against various microbial groups (aerobic mesophilic bacteria, enterococci, mesophilic lactobacilli, enterobacteriaceae, lactococcus and yeasts). Microbial groups were counted during ripening period using plate count on specific culture media. Organoleptic evaluation including teture, flavor, odor, color and total acceptability were determined at the end of aging. According to results, the essential oil yield was 4/1 % ( W/ W). Twenty- six compounds were identified in the oil that concluded 99.7 % of the total oil. The major components of Bunium persicum Boiss. essential oil were γ- terpinene- 7- al (26.9 %) and cuminaldehyde (23.3 %). Generally, the increase of Black Cumin essential oil concentration led to reduction in microbial counts in different groups. The maximum antimicrobial effect was seen in yeast that reduced by 2 log compared to the control group at EO concentration of 4µl/ ml at day 90.The minimum reduction was observed in enterobacteriaceae that showed only 0.75 log decreese compared to the control at the same concentration of EO. Addition of EO improved organoleptic properties of Gouda cheese especially in the case of flavor and odor characteristic. However, no significant differences were observed in texture and color between treatment and control groups. Bunium persicum Boiss. essential oil could be used as preservative material and flavoring agent in some kinds of food such as cheese and also could be provided consumers health.

Keywords: Bunium persicum Boiss. essential oil, Microbiological properties, sensory evaluation, gouda cheese

Procedia PDF Downloads 325