Search results for: normal glomerular filtration rate
294 Comparative Evaluation of High Pure Mn3O4 Preparation Technique between the Conventional Process from Electrolytic Manganese and a Sustainable Approach Directly from Low-Grade Rhodochrosite
Authors: Fang Lian, Zefang Chenli, Laijun Ma, Lei Mao
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Up to now, electrolytic process is a popular way to prepare Mn and MnO2 (EMD) with high purity. However, the conventional preparation process of manganese oxide such as Mn3O4 with high purity from electrolytic manganese metal is characterized by long production-cycle, high-pollution discharge and high energy consumption especially initially from low-grade rhodochrosite, the main resources for exploitation and applications in China. Moreover, Mn3O4 prepared from electrolytic manganese shows large particles, single morphology beyond the control and weak chemical activity. On the other hand, hydrometallurgical method combined with thermal decomposition, hydrothermal synthesis and sol-gel processes has been widely studied because of its high efficiency, low consumption and low cost. But the key problem in direct preparation of manganese oxide series from low-grade rhodochrosite is to remove completely the multiple impurities such as iron, silicon, calcium and magnesium. It is urgent to develop a sustainable approach to high pure manganese oxide series with character of short process, high efficiency, environmentally friendly and economical benefit. In our work, the preparation technique of high pure Mn3O4 directly from low-grade rhodochrosite ore (13.86%) was studied and improved intensively, including the effective leaching process and the short purifying process. Based on the same ion effect, the repeated leaching of rhodochrosite with sulfuric acid is proposed to improve the solubility of Mn2+ and inhibit the dissolution of the impurities Ca2+ and Mg2+. Moreover, the repeated leaching process could make full use of sulfuric acid and lower the cost of the raw material. With the aid of theoretical calculation, Ba(OH)2 was chosen to adjust the pH value of manganese sulfate solution and BaF2 to remove Ca2+ and Mg2+ completely in the process of purifying. Herein, the recovery ratio of manganese and removal ratio of the impurity were evaluated via chemical titration and ICP analysis, respectively. Comparison between conventional preparation technique from electrolytic manganese and a sustainable approach directly from low-grade rhodochrosite have also been done herein. The results demonstrate that the extraction ratio and the recovery ratio of manganese reached 94.3% and 92.7%, respectively. The heavy metal impurities has been decreased to less than 1ppm, and the content of calcium, magnesium and sodium has been decreased to less than 20ppm, which meet standards of high pure reagent for energy and electronic materials. In compare with conventional technique from electrolytic manganese, the power consumption has been reduced to ≤2000 kWh/t(product) in our short-process approach. Moreover, comprehensive recovery rate of manganese increases significantly, and the wastewater generated from our short-process approach contains low content of ammonia/ nitrogen about 500 mg/t(product) and no toxic emissions. Our study contributes to the sustainable application of low-grade manganese ore. Acknowledgements: The authors are grateful to the National Science and Technology Support Program of China (No.2015BAB01B02) for financial support to the work.Keywords: leaching, high purity, low-grade rhodochrosite, manganese oxide, purifying process, recovery ratio
Procedia PDF Downloads 246293 A Comparative Assessment of Information Value, Fuzzy Expert System Models for Landslide Susceptibility Mapping of Dharamshala and Surrounding, Himachal Pradesh, India
Authors: Kumari Sweta, Ajanta Goswami, Abhilasha Dixit
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Landslide is a geomorphic process that plays an essential role in the evolution of the hill-slope and long-term landscape evolution. But its abrupt nature and the associated catastrophic forces of the process can have undesirable socio-economic impacts, like substantial economic losses, fatalities, ecosystem, geomorphologic and infrastructure disturbances. The estimated fatality rate is approximately 1person /100 sq. Km and the average economic loss is more than 550 crores/year in the Himalayan belt due to landslides. This study presents a comparative performance of a statistical bivariate method and a machine learning technique for landslide susceptibility mapping in and around Dharamshala, Himachal Pradesh. The final produced landslide susceptibility maps (LSMs) with better accuracy could be used for land-use planning to prevent future losses. Dharamshala, a part of North-western Himalaya, is one of the fastest-growing tourism hubs with a total population of 30,764 according to the 2011 census and is amongst one of the hundred Indian cities to be developed as a smart city under PM’s Smart Cities Mission. A total of 209 landslide locations were identified in using high-resolution linear imaging self-scanning (LISS IV) data. The thematic maps of parameters influencing landslide occurrence were generated using remote sensing and other ancillary data in the GIS environment. The landslide causative parameters used in the study are slope angle, slope aspect, elevation, curvature, topographic wetness index, relative relief, distance from lineaments, land use land cover, and geology. LSMs were prepared using information value (Info Val), and Fuzzy Expert System (FES) models. Info Val is a statistical bivariate method, in which information values were calculated as the ratio of the landslide pixels per factor class (Si/Ni) to the total landslide pixel per parameter (S/N). Using this information values all parameters were reclassified and then summed in GIS to obtain the landslide susceptibility index (LSI) map. The FES method is a machine learning technique based on ‘mean and neighbour’ strategy for the construction of fuzzifier (input) and defuzzifier (output) membership function (MF) structure, and the FR method is used for formulating if-then rules. Two types of membership structures were utilized for membership function Bell-Gaussian (BG) and Trapezoidal-Triangular (TT). LSI for BG and TT were obtained applying membership function and if-then rules in MATLAB. The final LSMs were spatially and statistically validated. The validation results showed that in terms of accuracy, Info Val (83.4%) is better than BG (83.0%) and TT (82.6%), whereas, in terms of spatial distribution, BG is best. Hence, considering both statistical and spatial accuracy, BG is the most accurate one.Keywords: bivariate statistical techniques, BG and TT membership structure, fuzzy expert system, information value method, machine learning technique
Procedia PDF Downloads 121292 An Economic Way to Toughen Poly Acrylic Acid Superabsorbent Polymer Using Hyper Branched Polymer
Authors: Nazila Dehbari, Javad Tavakoli, Yakani Kambu, Youhong Tang
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Superabsorbent hydrogels (SAP), as an enviro-sensitive material have been widely used for industrial and biomedical applications due to their unique structure and capabilities. Poor mechanical properties of SAPs - which is extremely related to their large volume change – count as a great weakness in adopting for high-tech applications. Therefore, improving SAPs’ mechanical properties via toughening methods by mixing different types of cross-linked polymer or introducing energy-dissipating mechanisms is highly focused. In this work, in order to change the intrinsic brittle character of commercialized Poly Acrylic Acid (here as SAP) to be semi-ductile, a commercial available highly branched tree-like dendritic polymers with numerous –OH end groups known as hyper-branched polymer (HB) has been added to PAA-SAP system in a single step, cost effective and environment friendly solvent casting method. Samples were characterized by FTIR, SEM and TEM and their physico-chemical characterization including swelling capabilities, hydraulic permeability, surface tension and thermal properties had been performed. Toughness energy, stiffness, elongation at breaking point, viscoelastic properties and samples extensibility were mechanical properties that had been performed and characterized as a function of samples lateral cracks’ length in different HB concentration. Addition of HB to PAA-SAP significantly improved mechanical and surface properties. Increasing equilibrium swelling ratio by about 25% had been experienced by the SAP-HB samples in comparison with SAPs; however, samples swelling kinetics remained without changes as initial rate of water uptake and equilibrium time haven’t been subjected to any changes. Thermal stability analysis showed that HB is participating in hybrid network formation while improving mechanical properties. Samples characterization by TEM showed that, the aggregated HB polymer binders into nano-spheres with diameter in range of 10–200 nm. So well dispersion in the SAP matrix occurred as it was predictable due to the hydrophilic character of the numerous hydroxyl groups at the end of HB which enhance the compatibility of HB with PAA-SAP. As the profused -OH groups in HB could react with -COOH groups in the PAA-SAP during the curing process, the formation of a 2D structure in the SAP-HB could be attributed to the strong interfacial adhesion between HB and the PAA-SAP matrix which hinders the activity of PAA chains (SEM analysis). FTIR spectra introduced new peaks at 1041 and 1121 cm-1 that attributed to the C–O(–OH) stretching hydroxyl and O–C stretching ester groups of HB polymer binder indicating the incorporation of HB polymer into the SAP structure. SAP-HB polymer has significant effects on the final mechanical properties. The brittleness of PAA hydrogels are decreased by introducing HB as the fracture energies of hydrogels increased from 8.67 to 26.67. PAA-HBs’ stretch ability enhanced about 10 folds while reduced as a function of different notches depth.Keywords: superabsorbent polymer, toughening, viscoelastic properties, hydrogel network
Procedia PDF Downloads 318291 Medical and Dietary Potentials of Mare's Milk in Liver Diseases
Authors: Bakytzhan Bimbetov, Abay Zhangabilov, Saule Aitbaeva, Galymzhan Meirambekov
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Mare’s milk (saumal) contains in total about 40 biological components necessary for the human body. The most significant among them are amino acids, fats, carbohydrates, enzymes (lysozyme, amylase), more minerals and vitamins which are well balanced with each other. In Kazakhstan, Company "Eurasia Invest Ltd.” produces a freeze-dried saumal in form of powder by the use of modern German innovative technology by means of evaporating at low temperature (-35°C) with an appropriate pasteurization. Research of freeze-dried biomilk for the qualitative content showed that main ingredients of freshly drown milk are being preserved. We are currently studying medical and dietary properties of freeze-dried mare's milk for diseases of the digestive system, including for nonalcoholic steatohepatitis (NASH) and liver cirrhosis (LC) viral etiology. The studied group consisted of 14 patients with NASH, and 7 patients with LC viral etiology of Class A severity degree as per Child-Pugh. Patients took freeze-dried saumal, preliminary dissolved in boiled warm water (24 g. powder per 200 ml water) 3-4 times a day for a month in conjunction with basic therapy. The results were compared to a control group (11 patients with NASH and LC) who received only basic therapy without mare’s milk. Results of preliminary research showed an improvement of subjective and objective conditions of all patients, but more significant improvement of clinical symptoms and syndromes were observed in the treatment group compared to the control one. Patients with NASH significantly over time compared to the beginning of therapy decreased asthenic and dyspeptic syndromes (p<0,01). Hepatomegaly, identified on the basis of ultrasound prior to treatment was observed in 92,8±2,4% of patients, and after combination therapy hepatomegaly the rate decreased by 14,3%, amounting to 78,5±2,8%. Patients with LC also noted the improvement of asthenic (p<0,01) and dyspeptic (p<0,05) syndromes and hemorrhagic syndrome (nosebleeds and bleeding gums when brushing your teeth, p<0,05), and jaundice. Laboratory study also showed improvement in the research group, but more significant changes were observed in the experimental group. Group of patients with NASH showed a significant improvement of index in cytolysis in conjunction with a combination therapy (p<0,05). In the control group, these indicators were also improved, but they were not statistically reliable (p>0,05). Markers of liver failure were additionally studied during the study of laboratory parameters in patients with liver cirrhosis, in particular, bilirubin, albumin and prothrombin index (PTI). Combined therapy with the use of basic treatment and mare's milk showed a significant improvement in cytolysis and bilirubin (p<0,05). In our opinion, a very important and interesting fact is that, in conjunction with basic therapy, the use of mare's milk revealed an improvement of liver function in the form of normalized PTI and albumin in patients with liver cirrhosis viral etiology. Results of this work have shown therapeutic efficiency of the use of mare's milk in complex treatment of patients with liver disease and require further in-depth study.Keywords: liver cirrhosis, non-alcohol steatohepatitis, saumal, mare’s milk
Procedia PDF Downloads 225290 Electrical Decomposition of Time Series of Power Consumption
Authors: Noura Al Akkari, Aurélie Foucquier, Sylvain Lespinats
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Load monitoring is a management process for energy consumption towards energy savings and energy efficiency. Non Intrusive Load Monitoring (NILM) is one method of load monitoring used for disaggregation purposes. NILM is a technique for identifying individual appliances based on the analysis of the whole residence data retrieved from the main power meter of the house. Our NILM framework starts with data acquisition, followed by data preprocessing, then event detection, feature extraction, then general appliance modeling and identification at the final stage. The event detection stage is a core component of NILM process since event detection techniques lead to the extraction of appliance features. Appliance features are required for the accurate identification of the household devices. In this research work, we aim at developing a new event detection methodology with accurate load disaggregation to extract appliance features. Time-domain features extracted are used for tuning general appliance models for appliance identification and classification steps. We use unsupervised algorithms such as Dynamic Time Warping (DTW). The proposed method relies on detecting areas of operation of each residential appliance based on the power demand. Then, detecting the time at which each selected appliance changes its states. In order to fit with practical existing smart meters capabilities, we work on low sampling data with a frequency of (1/60) Hz. The data is simulated on Load Profile Generator software (LPG), which was not previously taken into consideration for NILM purposes in the literature. LPG is a numerical software that uses behaviour simulation of people inside the house to generate residential energy consumption data. The proposed event detection method targets low consumption loads that are difficult to detect. Also, it facilitates the extraction of specific features used for general appliance modeling. In addition to this, the identification process includes unsupervised techniques such as DTW. To our best knowledge, there exist few unsupervised techniques employed with low sampling data in comparison to the many supervised techniques used for such cases. We extract a power interval at which falls the operation of the selected appliance along with a time vector for the values delimiting the state transitions of the appliance. After this, appliance signatures are formed from extracted power, geometrical and statistical features. Afterwards, those formed signatures are used to tune general model types for appliances identification using unsupervised algorithms. This method is evaluated using both simulated data on LPG and real-time Reference Energy Disaggregation Dataset (REDD). For that, we compute performance metrics using confusion matrix based metrics, considering accuracy, precision, recall and error-rate. The performance analysis of our methodology is then compared with other detection techniques previously used in the literature review, such as detection techniques based on statistical variations and abrupt changes (Variance Sliding Window and Cumulative Sum).Keywords: electrical disaggregation, DTW, general appliance modeling, event detection
Procedia PDF Downloads 70289 Antimicrobial Properties of SEBS Compounds with Zinc Oxide and Zinc Ions
Authors: Douglas N. Simões, Michele Pittol, Vanda F. Ribeiro, Daiane Tomacheski, Ruth M. C. Santana
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The increasing demand of thermoplastic elastomers is related to the wide range of applications, such as automotive, footwear, wire and cable industries, adhesives and medical devices, cell phones, sporting goods, toys and others. These materials are susceptible to microbial attack. Moisture and organic matter present in some areas (such as shower area and sink), provide favorable conditions for microbial proliferation, which contributes to the spread of diseases and reduces the product life cycle. Compounds based on SEBS copolymers, poly(styrene-b-(ethylene-co-butylene)-b-styrene, are a class of thermoplastic elastomers (TPE), fully recyclable and largely used in domestic appliances like bath mats and tooth brushes (soft touch). Zinc oxide and zinc ions loaded in personal and home care products have become common in the last years due to its biocidal effect. In that sense, the aim of this study was to evaluate the effect of zinc as antimicrobial agent in compounds based on SEBS/polypropylene/oil/ calcite for use as refrigerator seals (gaskets), bath mats and sink squeegee. Two zinc oxides from different suppliers (ZnO-Pe and ZnO-WR) and one masterbatch of zinc ions (M-Zn-ion) were used in proportions of 0%, 1%, 3% and 5%. The compounds were prepared using a co-rotating double screw extruder (L/D ratio of 40/1 and 16 mm screw diameter). The extrusion parameters were kept constant for all materials. Tests specimens were prepared using the injection molding machine. A compound with no antimicrobial additive (standard) was also tested. Compounds were characterized by physical (density), mechanical (hardness and tensile properties) and rheological properties (melt flow rate - MFR). The Japan Industrial Standard (JIS) Z 2801:2010 was applied to evaluate antibacterial properties against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The Brazilian Association of Technical Standards (ABNT) NBR 15275:2014 were used to evaluate antifungal properties against Aspergillus niger (A. niger), Aureobasidium pullulans (A. pullulans), Candida albicans (C. albicans), and Penicillium chrysogenum (P. chrysogenum). The microbiological assay showed a reduction over 42% in E. coli and over 49% in S. aureus population. The tests with fungi showed inconclusive results because the sample without zinc also demonstrated an inhibition of fungal development when tested against A. pullulans, C. albicans and P. chrysogenum. In addition, the zinc loaded samples showed worse results than the standard sample when tested against A. niger. The zinc addition did not show significant variation in mechanical properties. However, the density values increased with the rise in ZnO additives concentration, and had a little decrease in M-Zn-ion samples. Also, there were differences in the MFR results in all compounds compared to the standard.Keywords: antimicrobial, home device, SEBS, zinc
Procedia PDF Downloads 318288 Strategic Planning Practice in a Global Perspective:the Case of Guangzhou, China
Authors: Shuyi Xie
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As the vital city in south China since the ancient time, Guangzhou has been losing its leading role among the rising neighboring cities, especially, Hong Kong and Shenzhen, since the late 1980s, with the overloaded infrastructure and deteriorating urban environment in its old inner city. Fortunately, with the new expansion of its administrative area in 2000, the local municipality considered it as a great opportunity to solve a series of alarming urban problems. Thus, for the first time, strategic planning was introduced to China for providing more convincing and scientific basis towards better urban future. Differed from traditional Chinese planning practices, which rigidly and dogmatically focused on future blueprints, the strategic planning of Guangzhou proceeded from analyzing practical challenges and opportunities towards establishing reasonable developing objectives and proposing corresponding strategies. Moreover, it was pioneering that the municipality invited five planning institutions for proposals, among which, the paper focuses on the one proposed by China Academy of Urban Planning & Design from its theoretical basis to problems’ defining and analyzing the process, as well as planning results. Since it was closer to the following municipal decisions and had a more far-reaching influence for other Chinese cities' following practices. In particular, it demonstrated an innovative exploration on the role played by urban developing rate on deciding urban growth patterns (‘Spillover-reverberation’ or ‘Leapfrog’). That ultimately established an unprecedented paradigm on deciding an appropriate urban spatial structure in future, including its specific location, function and scale. Besides the proposal itself, this article highlights the role of interactions, among actors, as well as proposals, subsequent discussions, summaries and municipal decisions, especially the establishment of the rolling dynamic evaluation system for periodical reviews on implementation situations, as the first attempt in China. Undoubtedly, strategic planning of Guangzhou has brought out considerable benefits, especially opening the strategic mind for plentiful Chinese cities in the following years through establishing a flexible and dynamic planning mechanism highlighted the interactions among multiple actors with innovative and effective tools, methodologies and perspectives on regional, objective-approach and comparative analysis. However, compared with some developed countries, the strategic planning in China just started and has been greatly relied on empirical studies rather than scientific analysis. Moreover, it still faced a bit of controversy, for instance, the certain gap among institutional proposals, final municipal decisions and implemented results, due to the lacking legal constraint. Also, how to improve the public involvement in China with an absolute up-down administrative system is another urgent task. In future, despite of irresistible and irretrievable weakness, some experiences and lessons from previous international practices, with the combination of specific Chinese situations and domestic practices, would enable to promote the further advance on strategic planning in China.Keywords: evaluation system, global perspective, Guangzhou, interactions, strategic planning, urban growth patterns
Procedia PDF Downloads 386287 Social Media Governance in UK Higher Education Institutions
Authors: Rebecca Lees, Deborah Anderson
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Whilst the majority of research into social media in education focuses on the applications for teaching and learning environments, this study looks at how such activities can be managed by investigating the current state of social media regulation within UK higher education. Social media has pervaded almost all aspects of higher education; from marketing, recruitment and alumni relations to both distance and classroom-based learning and teaching activities. In terms of who uses it and how it is used, social media is growing at an unprecedented rate, particularly amongst the target market for higher education. Whilst the platform presents opportunities not found in more traditional methods of communication and interaction, such as speed and reach, it also carries substantial risks that come with inappropriate use, lack of control and issues of privacy. Typically, organisations rely on the concept of a social contract to guide employee behaviour to conform to the expectations of that organisation. Yet, where academia and social media intersect applying the notion of a social contract to enforce governance may be problematic; firstly considering the emphasis on treating students as customers with a growing focus on the use and collection of satisfaction metrics; and secondly regarding the notion of academic’s freedom of speech, opinion and discussion, which is a long-held tradition of learning instruction. Therefore the need for sound governance procedures to support expectations over online behaviour is vital, especially when the speed and breadth of adoption of social media activities has in the past outrun organisations’ abilities to manage it. An analysis of the current level of governance was conducted by gathering relevant policies, guidelines and best practice documentation available online via internet search and institutional requests. The documents were then subjected to a content analysis in the second phase of this study to determine the approach taken by institutions to apply such governance. Documentation was separated according to audience, i.e.: applicable to staff, students or all users. Given many of these included guests and visitors to the institution within their scope being easily accessible was considered important. Yet, within the UK only about half of all education institutions had explicit social media governance documentation available online without requiring member access or considerable searching. Where they existed, the majority focused solely on employee activities and tended to be policy based rather than rooted in guidelines or best practices, or held a fallback position of governing online behaviour via implicit instructions within IT and computer regulations. Explicit instructions over expected online behaviours is therefore lacking within UK HE. Given the number of educational practices that now include significant online components, it is imperative that education organisations keep up to date with the progress of social media use. Initial results from the second phase of this study which analyses the content of the governance documentation suggests they require reading levels at or above the target audience, with some considerable variability in length and layout. Further analysis will add to this growing field of investigating social media governance within higher education.Keywords: governance, higher education, policy, social media
Procedia PDF Downloads 179286 Comparative Assessment of Rainwater Management Alternatives for Dhaka City: Case Study of North South University
Authors: S. M. Islam, Wasi Uddin, Nazmun Nahar
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Dhaka, the capital of Bangladesh, faces two contrasting problems; excess of water during monsoon season and scarcity of water during dry season. The first problem occurs due to rapid urbanization and mismanagement of rainwater whereas the second problem is related to climate change and increasing urban population. Inadequate drainage system also worsens the overall water management scenario in Dhaka city. Dhaka has a population density of 115,000 people per square miles. This results in a 2.5 billion liter water demand every day, 87% of which is fulfilled by groundwater. Over dependency on groundwater has resulted in more than 200 feet drop in the last 50 years and continues to decline at a rate of 9 feet per year. Considering the gravity of the problem, it is high time that practitioners, academicians and policymakers consider different water management practices and look into their cumulative impacts at different scales. The present study assesses different rainwater management options for North South University of Bangladesh and recommends the most feasible and sustainable rainwater management measure. North South University currently accommodates over 20,000 students, faculty members, and administrative staffs. To fulfill the water demand, there are two deep tube wells, which bring up approximately 150,000 liter of water every hour. The annual water demand is approximately 103 million liters. Dhaka receives approximately 1800 mm of rainfall every year. For the current study, two academic buildings and one administrative building consist of 4924 square meters of rooftop area was selected as catchment area. Both rainwater harvesting and groundwater recharge options were analyzed separately. It was estimated that by rainwater harvesting, annually a total of 7.2 million liters of water can be reused which is approximately 7% of the total annual water usage. In the monsoon, rainwater harvesting fulfills 12.2% of the monthly water demand. The approximate cost of the rainwater harvesting system is estimated to be 940975 bdt (USD 11500). For direct groundwater recharge, a system comprises of one de-siltation tank, two recharge tanks and one siltation tank were designed that requires approximately 532788 bdt (USD 6500). The payback period is approximately 7 years and 4 months for the groundwater recharge system whereas the payback period for rainwater harvesting option is approximately 12 years and 4 months. Based on the cost-benefit analysis, the present study finds the groundwater recharge system to be most suitable for North South University. The present study also demonstrates that if only one institution like North South University can add up a substantial amount of water to the aquifer, bringing other institutions in the network has the potential to create significant cumulative impact on replenishing the declining groundwater level of Dhaka city. As an additional benefit, it also prevents large amount of water being discharged into the storm sewers which results in severe flooding in Dhaka city during monsoon.Keywords: Dhaka, groundwater, harvesting, rainwater, recharge
Procedia PDF Downloads 119285 Anticancer Potentials of Aqueous Tinospora cordifolia and Its Bioactive Polysaccharide, Arabinogalactan on Benzo(a)Pyrene Induced Pulmonary Tumorigenesis: A Study with Relevance to Blood Based Biomarkers
Authors: Vandana Mohan, Ashwani Koul
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Aim: To evaluate the potential of Aqueous Tinospora cordifolia stem extract (Aq.Tc) and Arabinogalactan (AG) on pulmonary carcinogenesis and associated tumor markers. Background: Lung cancer is one of the most frequent malignancy with high mortality rate due to limitation of early detection resulting in low cure rates. Current research effort focuses on identifying some blood-based biomarkers like CEA, ctDNA and LDH which may have potential to detect cancer at an early stage, evaluation of therapeutic response and its recurrence. Medicinal plants and their active components have been widely investigated for their anticancer potentials. Aqueous preparation of T. Cordifolia extract is enriched in the polysaccharide fraction i.e., AG when compared with other types of extract. Moreover, reports are available of polysaccharide fraction of T. Cordifolia in in vitro lung cancer models which showed profound anti-metastatic activity against these cell lines. However, not much has been explored about its effect in in vivo lung cancer models and the underlying mechanism involved. Experimental Design: Mice were randomly segregated into six groups. Group I animals served as control. Group II animals were administered with Aq. Tc extract (200 mg/kg b.w.) p.o.on the alternate days. Group III animals were fed with AG (7.5 mg/kg b.w.) p.o. on the alternate days (thrice a week). Group IV animals were installed with Benzo(a)pyrene (50 mg/kg b.w.), i.p. twice within an interval of two weeks. Group V animals received Aq. Tc extract as in group II along with it B(a)P was installed after two weeks of Aq. Tc administration following the same protocol as for group IV. Group VI animals received AG as in group III along with it B(a)P was installed after two weeks of AG administration. Results: Administration of B(a)P to mice resulted in increased tumor incidence, multiplicity and pulmonary somatic index with concomitant increase in serum/plasma markers like CEA, ctDNA, LDH and TNF-α.Aq.Tc and AG supplementation significantly attenuated these alterations at different stages of tumorigenesis thereby showing potent anti-cancer effect in lung cancer. A pronounced decrease in serum/plasma markers were observed in animals treated with Aq.Tc as compared to those fed with AG. Also, extensive hyperproliferation of alveolar epithelium was prominent in B(a)P induced lung tumors. However, treatment of Aq.Tc and AG to lung tumor bearing mice exhibited reduced alveolar damage evident from decreased number of hyperchromatic irregular nuclei. A direct correlation between the concentration of tumor markers and the intensity of lung cancer was observed in animals bearing cancer co-treated with Aq.Tc and AG. Conclusion: These findings substantiate the chemopreventive potential of Aq.Tc and AG against lung tumorigenesis. Interestingly, Aq.Tc was found to be more effective in modulating the cancer as reflected by various observations which may be attributed to the synergism offered by various components of Aq.Tc. Further studies are in progress to understand the underlined mechanism in inhibiting lung tumorigenesis by Aq.Tc and AG.Keywords: Arabinogalactan, Benzo(a)pyrene B(a)P, carcinoembryonic antigen (CEA), circulating tumor DNA (ctDNA), lactate dehydrogenase (LDH), Tinospora cordifolia
Procedia PDF Downloads 178284 Thermal Ageing of a 316 Nb Stainless Steel: From Mechanical and Microstructural Analyses to Thermal Ageing Models for Long Time Prediction
Authors: Julien Monnier, Isabelle Mouton, Francois Buy, Adrien Michel, Sylvain Ringeval, Joel Malaplate, Caroline Toffolon, Bernard Marini, Audrey Lechartier
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Chosen to design and assemble massive components for nuclear industry, the 316 Nb austenitic stainless steel (also called 316 Nb) suits well this function thanks to its mechanical, heat and corrosion handling properties. However, these properties might change during steel’s life due to thermal ageing causing changes within its microstructure. Our main purpose is to determine if the 316 Nb will keep its mechanical properties after an exposition to industrial temperatures (around 300 °C) during a long period of time (< 10 years). The 316 Nb is composed by different phases, which are austenite as main phase, niobium-carbides, and ferrite remaining from the ferrite to austenite transformation during the process. Our purpose is to understand thermal ageing effects on the material microstructure and properties and to submit a model predicting the evolution of 316 Nb properties as a function of temperature and time. To do so, based on Fe-Cr and 316 Nb phase diagrams, we studied the thermal ageing of 316 Nb steel alloys (1%v of ferrite) and welds (10%v of ferrite) for various temperatures (350, 400, and 450 °C) and ageing time (from 1 to 10.000 hours). Higher temperatures have been chosen to reduce thermal treatment time by exploiting a kinetic effect of temperature on 316 Nb ageing without modifying reaction mechanisms. Our results from early times of ageing show no effect on steel’s global properties linked to austenite stability, but an increase of ferrite hardness during thermal ageing has been observed. It has been shown that austenite’s crystalline structure (cfc) grants it a thermal stability, however, ferrite crystalline structure (bcc) favours iron-chromium demixion and formation of iron-rich and chromium-rich phases within ferrite. Observations of thermal ageing effects on ferrite’s microstructure were necessary to understand the changes caused by the thermal treatment. Analyses have been performed by using different techniques like Atomic Probe Tomography (APT) and Differential Scanning Calorimetry (DSC). A demixion of alloy’s elements leading to formation of iron-rich (α phase, bcc structure), chromium-rich (α’ phase, bcc structure), and nickel-rich (fcc structure) phases within the ferrite have been observed and associated to the increase of ferrite’s hardness. APT results grant information about phases’ volume fraction and composition, allowing to associate hardness measurements to the volume fractions of the different phases and to set up a way to calculate α’ and nickel-rich particles’ growth rate depending on temperature. The same methodology has been applied to DSC results, which allowed us to measure the enthalpy of α’ phase dissolution between 500 and 600_°C. To resume, we started from mechanical and macroscopic measurements and explained the results through microstructural study. The data obtained has been match to CALPHAD models’ prediction and used to improve these calculations and employ them to predict 316 Nb properties’ change during the industrial process.Keywords: stainless steel characterization, atom probe tomography APT, vickers hardness, differential scanning calorimetry DSC, thermal ageing
Procedia PDF Downloads 88283 Women's Entrepreneurship in Mena Region: Gem Key Learnings
Authors: Fatima Boutaleb
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Entrepreneurship proves to be crucial for the economic growth and development, since it contributes to job creation and the improvement of the overall productivity thus generating a positive impact upon society at various levels. Promoting entrepreneurship stimulates therefore economic diversity that is key to the betterment and/or maintaining of the standard of living. In fact, recent research suggests that entrepreneurship contributes to development by creating businesses and jobs, stimulating innovation, creating social capital across borders, and channeling political and financial capital. However, different research studies indicate that among the main factors impeding the entrepreneurship are politico-economic as socio-cultural problems, with an intensity for those related to young people and to women. In the MENA region, discrimination inherent in gender is alarming: Only one woman in eight runs her own business against 1 in 3 men. In most countries, young women and young men are facing problems involving access to finance, inadequate infrastructure, lack of support and, in general, an ecosystem that is rather unfavorable. According to the International Labor Organization, North Africa and the Middle East has the highest unemployment rate in all other regions of the world. In other hand, nearly a quarter of the population under 30 is unemployed and youth unemployment costs more than $40 billion each year to the region. In the current context, the situations in the Middle East and North Africa region are singular, both in terms of demographic trends and socio-economic issues around the employment of a large and better trained youth, but still strongly affected by unemployment and under-employment. According to a study published in 2015 by McKinsey, the world gain 26% of additional GDP (47% in the MENA region), more than 28 trillion dollars by 2025, if women came to participate, as well as men, to the economy. Promoting entrepreneurship represents an excellent alternative for the countries whose productive fabric fails to integrate the contingent of young people entering the job market each year. The MENA region, presenting entrepreneurial activity rates below those of other regions in terms of comparable development, has undoubtedly leeway at this level, even though the region displays large national heterogeneity, namely in the priority given to the promotion of entrepreneurship. The objective of this article is therefore to examine the women entrepreneurial vocation in the MENA region, to see to what extent research on the determinant of gender can provide information on the trend of the emerging entrepreneurial activity whether driven by necessity or by opportunity and, on this basis, to submit public policy proposals for the improvement of the mechanisms of inclusion among the youth women people. The objective is not to analyze the causality models but rather to identify the entrepreneurial construct specific to the MENA region via the analysis of GEM data from 2017 to 2019 among adults belonging to 10 countries of the MENA region. Notably, the study shows that inclusion of young women may be enhanced. These disadvantaged segments frequently intend to become entrepreneurs, but they tend not to enact their vocational intentions.Keywords: economic development, entrepreneurial activity, GEM, gender, informal sector
Procedia PDF Downloads 96282 Frequency Decomposition Approach for Sub-Band Common Spatial Pattern Methods for Motor Imagery Based Brain-Computer Interface
Authors: Vitor M. Vilas Boas, Cleison D. Silva, Gustavo S. Mafra, Alexandre Trofino Neto
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Motor imagery (MI) based brain-computer interfaces (BCI) uses event-related (de)synchronization (ERS/ ERD), typically recorded using electroencephalography (EEG), to translate brain electrical activity into control commands. To mitigate undesirable artifacts and noise measurements on EEG signals, methods based on band-pass filters defined by a specific frequency band (i.e., 8 – 30Hz), such as the Infinity Impulse Response (IIR) filters, are typically used. Spatial techniques, such as Common Spatial Patterns (CSP), are also used to estimate the variations of the filtered signal and extract features that define the imagined motion. The CSP effectiveness depends on the subject's discriminative frequency, and approaches based on the decomposition of the band of interest into sub-bands with smaller frequency ranges (SBCSP) have been suggested to EEG signals classification. However, despite providing good results, the SBCSP approach generally increases the computational cost of the filtering step in IM-based BCI systems. This paper proposes the use of the Fast Fourier Transform (FFT) algorithm in the IM-based BCI filtering stage that implements SBCSP. The goal is to apply the FFT algorithm to reduce the computational cost of the processing step of these systems and to make them more efficient without compromising classification accuracy. The proposal is based on the representation of EEG signals in a matrix of coefficients resulting from the frequency decomposition performed by the FFT, which is then submitted to the SBCSP process. The structure of the SBCSP contemplates dividing the band of interest, initially defined between 0 and 40Hz, into a set of 33 sub-bands spanning specific frequency bands which are processed in parallel each by a CSP filter and an LDA classifier. A Bayesian meta-classifier is then used to represent the LDA outputs of each sub-band as scores and organize them into a single vector, and then used as a training vector of an SVM global classifier. Initially, the public EEG data set IIa of the BCI Competition IV is used to validate the approach. The first contribution of the proposed method is that, in addition to being more compact, because it has a 68% smaller dimension than the original signal, the resulting FFT matrix maintains the signal information relevant to class discrimination. In addition, the results showed an average reduction of 31.6% in the computational cost in relation to the application of filtering methods based on IIR filters, suggesting FFT efficiency when applied in the filtering step. Finally, the frequency decomposition approach improves the overall system classification rate significantly compared to the commonly used filtering, going from 73.7% using IIR to 84.2% using FFT. The accuracy improvement above 10% and the computational cost reduction denote the potential of FFT in EEG signal filtering applied to the context of IM-based BCI implementing SBCSP. Tests with other data sets are currently being performed to reinforce such conclusions.Keywords: brain-computer interfaces, fast Fourier transform algorithm, motor imagery, sub-band common spatial patterns
Procedia PDF Downloads 126281 Investigation of Hydrate Formation of Associated Petroleum Gas from Promoter Solutions for the Purpose of Utilization and Reduction of Its Burning
Authors: M. E. Semenov, U. Zh. Mirzakimov, A. S. Stoporev, R. S. Pavelev, M. A. Varfolomeev
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Gas hydrates are host-guest compounds. Guest molecules can be low molecular weight components of associated petroleum gas (C1-C4 hydrocarbons), carbon dioxide, hydrogen sulfide, and nitrogen. Gas hydrates have a number of unique properties that make them interesting from a technological point of view, for example, for storing hydrocarbon gases in solid form under moderate thermobaric conditions. Currently, the possibility of storing and transporting hydrocarbon gases in the form of solid hydrate is being actively explored throughout the world. The hydrate form of gas has a number of advantages, including a significant gas content in the hydrate, relative safety and environmental friendliness of the process. Recently, new developments have been proposed that seek to reduce the number of steps to obtain the finished hydrate, for example, using a pressing device/screw inside the reactor. However, the energy consumption required for the hydrate formation process remains a challenge. Thus, the goal of the current work is to study the patterns and mechanisms of the hydrate formation process using small additions of hydrate formation promoters under static conditions. The study of these aspects will help solve the problem of accelerated production of gas hydrates with minimal energy consumption. New compounds have been developed at Kazan Federal University that can accelerate the formation of methane hydrate with a small amount of promoter in water, not exceeding 0.1% by weight. These promoters were synthesized based on available natural compounds and showed high efficiency in accelerating the growth of methane hydrate. To test the influence of promoters on the process of hydrate formation, standard experiments are carried out under dynamic conditions with stirring. During such experiments, the time at which hydrate formation begins (induction period), the temperature at which formation begins (supercooling), the rate of hydrate formation, and the degree of conversion of water to hydrate are assessed. This approach helps to determine the most effective compound in comparative experiments with different promoters and select their optimal concentration. These experimental studies made it possible to study the features of the formation of associated petroleum gas hydrate from promoter solutions under static conditions. Phase transformations were studied using high-pressure micro-differential scanning calorimetry under various experimental conditions. Visual studies of the growth mode of methane hydrate depending on the type of promoter were also carried out. The work is an extension of the methodology for studying the effect of promoters on the process of associated petroleum gas hydrate formation in order to identify new ways to accelerate the formation of gas hydrates without the use of mixing. This work presents the results of a study of the process of associated petroleum gas hydrate formation using high-pressure differential scanning micro-calorimetry, visual investigation, gas chromatography, autoclaves study, and stability data. It was found that the synthesized compounds multiply the conversion of water into hydrate under static conditions up to 96% due to a change in the growth mechanism of associated petroleum gas hydrate.Keywords: gas hydrate, gas storage, promotor, associated petroleum gas
Procedia PDF Downloads 58280 The Relationship between Depression, HIV Stigma and Adherence to Antiretroviral Therapy among Adult Patients Living with HIV at a Tertiary Hospital in Durban, South Africa: The Mediating Roles of Self-Efficacy and Social Support
Authors: Muziwandile Luthuli
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Although numerous factors predicting adherence to antiretroviral therapy (ART) among people living with HIV/AIDS (PLWHA) have been broadly studied on both regional and global level, up-to-date adherence of patients to ART remains an overarching, dynamic and multifaceted problem that needs to be investigated over time and across various contexts. There is a rarity of empirical data in the literature on interactive mechanisms by which psychosocial factors influence adherence to ART among PLWHA within the South African context. Therefore, this study was designed to investigate the relationship between depression, HIV stigma, and adherence to ART among adult patients living with HIV at a tertiary hospital in Durban, South Africa, and the mediating roles of self-efficacy and social support. The health locus of control theory and the social support theory were the underlying theoretical frameworks for this study. Using a cross-sectional research design, a total of 201 male and female adult patients aged between 18-75 years receiving ART at a tertiary hospital in Durban, KwaZulu-Natal were sampled, using time location sampling (TLS). A self-administered questionnaire was employed to collect the data in this study. Data were analysed through SPSS version 27. Several statistical analyses were conducted in this study, namely univariate statistical analysis, correlational analysis, Pearson’s chi-square analysis, cross-tabulation analysis, binary logistic regression analysis, and mediational analysis. Univariate analysis indicated that the sample mean age was 39.28 years (SD=12.115), while most participants were females 71.0% (n=142), never married 74.2% (n=147), and most were also secondary school educated 48.3% (n=97), as well as unemployed 65.7% (n=132). The prevalence rate of participants who had high adherence to ART was 53.7% (n=108), and 46.3% (n=93) of participants had low adherence to ART. Chi-square analysis revealed that employment status was the only statistically significant socio-demographic influence of adherence to ART in this study (χ2 (3) = 8.745; p < .033). Chi-square analysis showed that there was a statistically significant difference found between depression and adherence to ART (χ2 (4) = 16.140; p < .003), while between HIV stigma and adherence to ART, no statistically significant difference was found (χ2 (1) = .323; p >.570). Binary logistic regression indicated that depression was statistically associated with adherence to ART (OR= .853; 95% CI, .789–.922, P < 001), while the association between self-efficacy and adherence to ART was statistically significant (OR= 1.04; 95% CI, 1.001– 1.078, P < .045) after controlling for the effect of depression. However, the findings showed that the effect of depression on adherence to ART was not significantly mediated by self-efficacy (Sobel test for indirect effect, Z= 1.01, P > 0.31). Binary logistic regression showed that the effect of HIV stigma on adherence to ART was not statistically significant (OR= .980; 95% CI, .937– 1.025, P > .374), but the effect of social support on adherence to ART was statistically significant, only after the effect of HIV stigma was controlled for (OR= 1.017; 95% CI, 1.000– 1.035, P < .046). This study promotes behavioral and social change effected through evidence-based interventions by emphasizing the need for additional research that investigates the interactive mechanisms by which psychosocial factors influence adherence to ART. Depression is a significant predictor of adherence to ART. Thus, to alleviate the psychosocial impact of depression on adherence to ART, effective interventions must be devised, along with special consideration of self-efficacy and social support. Therefore, this study is helpful in informing and effecting change in health policy and healthcare services through its findingsKeywords: ART adherence, depression, HIV/AIDS, PLWHA
Procedia PDF Downloads 176279 Prevalence, Antimicrobial Susceptibility Pattern and Public Health Significance for Staphylococcus aureus of Isolated From Raw Red Meat at Butchery and Abattoir House in Mekelle, Northern Ethiopia
Authors: Haftay Abraha Tadesse
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Background: Staphylococcus is a genus of worldwide distributed bacteria correlated to several infectious of different sites in human and animals. They are among the most important causes of infection that are associated with the consumption of contaminated food. Objective: The objective of this study was to determine the isolates, antimicrobial susceptibility patterns and public health significance for Staphylococcus aureus in raw meat from butchery and abattoir houses of Mekelle, Northern Ethiopia. Methodology: A cross-sectional study was conducted from April to October 2019. Sociodemographic data and public health significance were collected using predesigned questionnaire. The raw meat samples were collected aseptically in the butchery and abattoir houses and transported using ice box to Mekelle University, College of Veterinary Sciences for isolating and identification of Staphylococcus aureus. Antimicrobial susceptibility tests were determined by disc diffusion method. Data obtained were cleaned and entered in to STATA 22.0 and logistic regression model with odds ratio were calculated to assess the association of risk factors with bacterial contamination. P-value < 0.05 was considered as statistically significant. Results: In present study, 88 out of 250 (35.2%) were found to be contamination with Staphylococcus aureus. Among the raw meat specimens to be positivity rate of Staphylococcus aureus were 37.6% (n=47) and (32.8% (n=41), butchery and abattoir houses, respectively. Among the associated risk factories not using gloves reduces risk was found to (AOR=0.222; 95% CI: 0.104-0.473), Strict Separation b/n clean & dirty (AOR= 1.37; 95% CI: 0.66-2.86) and poor habit of hand washing (AOR=1.08; 95%CI: 0.35-3.35) were found to be statistically significant and ha ve associated with Staphylococcus aureus contamination. All isolates thirty sevevn of Staphyloco ccus aureus were checked displayed (100%) sensitive to doxycycline, trimethoprim, gentamicin, sulphamethoxazole, amikacin, CN, Co trimoxazole and nitrofurantoi. whereas the showed resistance of cefotaxime (100%), ampicillin (87.5%), Penicillin (75%), B (75%), and nalidixic acid (50%) from butchery houses. On the other hand, all isolates of Staphylococcus aur eu isolate 100% (n= 10) showed sensitive chloramphenicol, gentamicin and nitrofurantoin whereas the showed 100% resistance of Penicillin, B, AMX, ceftriaxone, ampicillin and cefotaxime from abattoirs houses. The overall multi drug resistance pattern for Staphylococcus aureus were 90% and 100% of butchery and abattoirs houses, respectively. Conclusion: 35.3% Staphylococcus aureus isolated were recovered from the raw meat samples collected from the butchery and abattoirs houses. More has to be done in the developed of hand washing behavior, and availability of safe water in the butchery houses to reduce burden of bacterial contamination. The results of the present finding highlight the need to implement protective measures against the levels of food contamination and alternative drug options. The development of antimicrobial resistance is nearly always as a result of repeated therapeutic and/or indiscriminate use of them. Regular antimicrobial sensitivity testing helps to select effective antibiotics and to reduce the problems of drug resistance development towards commonly used antibiotics. Key words: abattoir houses, antimicrobial resistance, butchery houses, Ethiopia,Keywords: abattoir houses, antimicrobial resistance, butchery houses, Ethiopia, staphylococcus aureuse, MDR
Procedia PDF Downloads 60278 Premature Departure of Active Women from the Working World: One Year Retrospective Study in the Tunisian Center
Authors: Lamia Bouzgarrou, Amira Omrane, Malika Azzouzi, Asma Kheder, Amira Saadallah, Ilhem Boussarsar, Kamel Rejeb
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Introduction: Increasing the women’s labor force participation is a political issue in countries with developed economies and those with low growth prospects. However, in the labor market, women continue to face several obstacles, either for the integration or for the maintenance at work. This study aims to assess the prevalence of premature withdrawal from working life -due to invalidity or medical justified early retirement- among active women in the Tunisian center and to identify its determinants. Material and methods: We conducted a cross-sectional study, over one year, focusing on the agreement for invalidity or early retirement for premature usury of the body- delivered by the medical commission of the National Health Insurance Fund (CNAM) in the central Tunisian district. We exhaustively selected women's files. Data related to Socio-demographic characteristics, professional and medical ones, were collected from the CNAM's administrative and medical files. Results: During the period of one year, 222 women have had an agreement for premature departure of their professional activity. Indeed, 149 women (67.11%) benefit of from invalidity agreement and 20,27% of them from favorable decision for early retirement. The average age was 50 ± 6 years with extremes of 23 and 62 years, and 18.9% of women were under 45 years. Married women accounted for 69.4% and 59.9% of them had at least one dependent child in charge. The average professional seniority in the sector was 23 ± 8 years. The textile-clothing sector was the most affected, with 70.7% of premature departure. Medical reasons for withdrawal from working life were mainly related to neuro-degenerative diseases in 46.8% of cases, rheumatic ones in 35.6% of cases and cardiovascular diseases in 22.1% of them. Psychiatric and endocrine disorders motivated respectively 17.1% and 13.5% of these departures. The evaluation of the sequels induced by these pathologies concluded to an average permanent partial disability equal to 61.4 ± 17.3%. The analytical study concluded that the agreement of disability or early retirement was correlated with the insured ‘age (p = 10-3), the professional seniority (p = 0.003) and the permanent partial incapacity (PPI) rate assessed by the expert physician (p = 0.04). No other social or professional factors were correlated with this decision. Conclusion: Despite many advances in labour law and Tunisian legal text on employability, women still exposed to several social and professional inequalities (payment inequality, precarious work ...). Indeed, women are often pushed to accept working in adverse conditions, thus they are more vulnerable to develop premature wear on the body and being forced to premature departures from the world of work. These premature withdrawals from active life are not only harmful to the concerned women themselves, but also associated with considerable costs for the insurance organism and the society. In order to ensure maintenance at work for women, a political commitment is imperative in the implementation of global prevention strategies and the improvement of working conditions, particularly in our socio-cultural context.Keywords: Active Women , Early Retirement , Invalidity , Maintenance at Work
Procedia PDF Downloads 147277 Surface Acoustic Waves Nebulisation of Liposomes Manufactured in situ for Pulmonary Drug Delivery
Authors: X. King, E. Nazarzadeh, J. Reboud, J. Cooper
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Pulmonary diseases, such as asthma, are generally treated by the inhalation of aerosols that has the advantage of reducing the off-target (e.g., toxicity) effects associated with systemic delivery in blood. Effective respiratory drug delivery requires a droplet size distribution between 1 and 5 µm. Inhalation of aerosols with wide droplet size distribution, out of this range, results in deposition of drug in not-targeted area of the respiratory tract, introducing undesired side effects on the patient. In order to solely deliver the drug in the lower branches of the lungs and release it in a targeted manner, a control mechanism to produce the aerosolized droplets is required. To regulate the drug release and to facilitate the uptake from cells, drugs are often encapsulated into protective liposomes. However, a multistep process is required for their formation, often performed at the formulation step, therefore limiting the range of available drugs or their shelf life. Using surface acoustic waves (SAWs), a pulmonary drug delivery platform was produced, which enabled the formation of defined size aerosols and the formation of liposomes in situ. SAWs are mechanical waves, propagating along the surface of a piezoelectric substrate. They were generated using an interdigital transducer on lithium niobate with an excitation frequency of 9.6 MHz at a power of 1W. Disposable silicon superstrates were etched using photolithography and dry etch processes to create an array of cylindrical through-holes with different diameters and pitches. Superstrates were coupled with the SAW substrate through water-based gel. As the SAW propagates on the superstrate, it enables nebulisation of a lipid solution deposited onto it. The cylindrical cavities restricted the formation of large drops in the aerosol, while at the same time unilamellar liposomes were created. SAW formed liposomes showed a higher monodispersity compared to the control sample, as well as displayed, a faster production rate. To test the aerosol’s size, dynamic light scattering and laser diffraction methods were used, both showing the size control of the aerosolised particles. The use of silicon superstate with cavity size of 100-200 µm, produced an aerosol with a mean droplet size within the optimum range for pulmonary drug delivery, containing the liposomes in which the medicine could be loaded. Additionally, analysis of liposomes with Cryo-TEM showed formation of vesicles with narrow size distribution between 80-100 nm and optimal morphology in order to be used for drug delivery. Encapsulation of nucleic acids in liposomes through the developed SAW platform was also investigated. In vitro delivery of siRNA and DNA Luciferase were achieved using A549 cell line, lung carcinoma from human. In conclusion, SAW pulmonary drug delivery platform was engineered, in order to combine multiple time consuming steps (formation of liposomes, drug loading, nebulisation) into a unique platform with the aim of specifically delivering the medicament in a targeted area, reducing the drug’s side effects.Keywords: acoustics, drug delivery, liposomes, surface acoustic waves
Procedia PDF Downloads 118276 Temporal Variation of Surface Runoff and Interrill Erosion in Different Soil Textures of a Semi-arid Region, Iran
Authors: Ali Reza Vaezi, Naser Fakori Ivand, Fereshteh Azarifam
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Interrill erosion is the detachment and transfer of soil particles between the rills due to the impact of raindrops and the shear stress of shallow surface runoff. This erosion can be affected by some soil properties such as texture, amount of organic matter and stability of soil aggregates. Information on the temporal variation of interrill erosion during a rainfall event and the effect soil properties have on it can help in understanding the process of runoff production and soil loss between the rills in hillslopes. The importance of this study is especially grate in semi-arid regions, where the soil is weakly aggregated and vegetation cover is mostly poor. Therefore, this research was conducted to investigate the temporal variation of surface flow and interrill erosion and the effect of soil properties on it in some semi-arid soils. A field experiment was done in eight different soil textures under simulated rainfalls with uniform intensity. A total of twenty four plots were installed for eight study soils with three replicates in the form of a random complete block design along the land. The plots were 1.2 m (length) × 1 m (width) in dimensions which designed with a distance of 3 m from each other across the slope. Then, soil samples were purred into the plots. The plots were surrounded by a galvanized sheet, and runoff and soil erosion equipment were placed at their outlets. Rainfall simulation experiments were done using a designed portable simulator with an intensity of 60 mm per hour for 60 minutes. A plastic cover was used around the rainfall simulator frame to prevent the impact of the wind on the free fall of water drops. Runoff production and soil loss were measured during 1 hour time with 5-min intervals. In order to study soil properties, such as particle size distribution, aggregate stability, bulk density, ESP and Ks were determined in the laboratory. Correlation and regression analysis was done to determine the effect of soil properties on runoff and interrill erosion. Results indicated that the study soils have lower booth organic matter content and aggregate stability. The soils, except for coarse textured textures, are calcareous and with relatively higher exchangeable sodium percentages (ESP). Runoff production and soil loss didn’t occur in sand, which was associated with higher infiltration and drainage rates. In other study soils, interrill erosion occurred simultaneously with the generation of runoff. A strong relationship was found between interrill erosion and surface runoff (R2 = 0.75, p< 0.01). The correlation analysis showed that surface runoff was significantly affected by some soil properties consisting of sand, silt, clay, bulk density, gravel, hydraulic conductivity (Ks), lime (calcium carbonate), and ESP. The soils with lower Ks such as fine-textured soils, produced higher surface runoff and more interrill erosion. In the soils, Surface runoff production temporally increased during rainfall and finally reached a peak after about 25-35 min. Time to peak was very short (30 min) in fine-textured soils, especially clay, which was related to their lower infiltration rate.Keywords: erosion plot, rainfall simulator, soil properties, surface flow
Procedia PDF Downloads 55275 Density Determination of Liquid Niobium by Means of Ohmic Pulse-Heating for Critical Point Estimation
Authors: Matthias Leitner, Gernot Pottlacher
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Experimental determination of critical point data like critical temperature, critical pressure, critical volume and critical compressibility of high-melting metals such as niobium is very rare due to the outstanding experimental difficulties in reaching the necessary extreme temperature and pressure regimes. Experimental techniques to achieve such extreme conditions could be diamond anvil devices, two stage gas guns or metal samples hit by explosively accelerated flyers. Electrical pulse-heating under increased pressures would be another choice. This technique heats thin wire samples of 0.5 mm diameter and 40 mm length from room temperature to melting and then further to the end of the stable phase, the spinodal line, within several microseconds. When crossing the spinodal line, the sample explodes and reaches the gaseous phase. In our laboratory, pulse-heating experiments can be performed under variation of the ambient pressure from 1 to 5000 bar and allow a direct determination of critical point data for low-melting, but not for high-melting metals. However, the critical point also can be estimated by extrapolating the liquid phase density according to theoretical models. A reasonable prerequisite for the extrapolation is the existence of data that cover as much as possible of the liquid phase and at the same time exhibit small uncertainties. Ohmic pulse-heating was therefore applied to determine thermal volume expansion, and from that density of niobium over the entire liquid phase. As a first step, experiments under ambient pressure were performed. The second step will be to perform experiments under high-pressure conditions. During the heating process, shadow images of the expanding sample wire were captured at a frame rate of 4 × 105 fps to monitor the radial expansion as a function of time. Simultaneously, the sample radiance was measured with a pyrometer operating at a mean effective wavelength of 652 nm. To increase the accuracy of temperature deduction, spectral emittance in the liquid phase is also taken into account. Due to the high heating rates of about 2 × 108 K/s, longitudinal expansion of the wire is inhibited which implies an increased radial expansion. As a consequence, measuring the temperature dependent radial expansion is sufficient to deduce density as a function of temperature. This is accomplished by evaluating the full widths at half maximum of the cup-shaped intensity profiles that are calculated from each shadow image of the expanding wire. Relating these diameters to the diameter obtained before the pulse-heating start, the temperature dependent volume expansion is calculated. With the help of the known room-temperature density, volume expansion is then converted into density data. The so-obtained liquid density behavior is compared to existing literature data and provides another independent source of experimental data. In this work, the newly determined off-critical liquid phase density was in a second step utilized as input data for the estimation of niobium’s critical point. The approach used, heuristically takes into account the crossover from mean field to Ising behavior, as well as the non-linearity of the phase diagram’s diameter.Keywords: critical point data, density, liquid metals, niobium, ohmic pulse-heating, volume expansion
Procedia PDF Downloads 215274 Strengthening Facility-Based Systems to Improve Access to In-Patient Care for Sick Newborns in Brong Ahafo Region, Ghana
Authors: Paulina Clara Appiah, Kofi Issah, Timothy Letsa, Kennedy Nartey, Amanua Chinbuah, Adoma Dwomo-Fokuo, Jacqeline G. Asibey
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Background: The Every Newborn Action Plan provides evidence–based interventions to end preventable deaths in high burden countries. Brong Ahafo Region is one of ten regions in Ghana with less than half of its district hospitals having sick newborn units. Facility-based neonatal care is not prioritized and under-funded, and there is also inadequate knowledge and competence to manage the sick. The aim of this intervention was to make available in–patient care for sick newborns in all 19 district hospitals through the strengthening of facility-based systems. Methods: With the development and dissemination of the National Newborn Strategy and Action Plan 2014-2018, the country was able to attract PATH which provided the region with basic resuscitation equipment, supported hospital providers’ capacity building in Helping Babies Breathe, Essential Care of Every Baby, Infection Prevention and Management and held a symposia on managing the sick newborn. Newborn advocacy was promoted through newborn champions at the facility and community levels. Hospital management was then able to mobilize resources from communities, corporate organizations and from internally generated funds; created or expanded sick newborn care units and provided essential medicines and equipment. Kangaroo Mother Care was initiated in 6 hospitals. Pediatric specialist outreach services initiated comprised telephone consultations, teaching ward rounds and participating in perinatal death audits meetings. Newborn data capture and management was improved through the provision and training on the use of standard registers provided from the national level. Results: From February 2015 to November 2017, hospitals with sick newborn units increased from 7 to 19 (37%-100%). 180 pieces each of newborn ventilation bags and masks size 0, 1 and penguin suction bulbs were distributed to the hospitals, in addition to 20 newborn mannequin sets and 90 small clinical reminder posters. 802 providers (96.9%) were trained in resuscitation, of which 96% were successfully followed up in 6 weeks, 91% in 6 months and 80% in 12 months post-training. 53 clinicians (65%) were trained and mentored to manage sick newborns. 56 specialist teaching ward rounds were conducted. Data completeness improved from 92.6% - 99.9%. Availability of essential medicines improved from 11% to 100%. Number of hospital cots increased from 116 to 248 (214%). Cot occupancy rate increased from 57.4% to 92.5%. Hospitals with phototherapy equipment increased from 0 to 12 (63%). Hospitals with incubators increased from 1 to 12 (5%-63%). Newborn deaths among admissions reduced from 6.3% to 5.4%. Conclusion: Access to in-patient care increased significantly. Newborn advocacy successfully mobilized resources required for strengthening facility –based systems.Keywords: facility-based systems, Ghana, in-patient care, newborn advocacy
Procedia PDF Downloads 228273 The Lacuna in Understanding of Forensic Science amongst Law Practitioners in India
Authors: Poulomi Bhadra, Manjushree Palit, Sanjeev P. Sahni
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Forensic science uses all branches of science for criminal investigation and trial and has increasingly emerged as an important tool in the administration of justice. However, the growth and development of this field in India has not been as rapid or widespread as compared to the more developed Western countries. For successful administration of justice, it is important that all agencies involved in law enforcement adopt an inter-professional approach towards forensic science, which is presently lacking. In light of the alarmingly high average acquittal rate in India, this study aims to examine the lack of understanding and appreciation of the importance and scope of forensic evidence and expert opinions amongst law professionals such as lawyers and judges. Based on a study of trial court cases from Delhi and surrounding areas, the study underline the areas in forensics where the criminal justice system has noticeably erred. Using this information, the authors examine the extent of forensic understanding amongst legal professionals and attempt to conclusively identify the areas in which they need further appraisal. A cross-sectional study done using a structured questionnaire was conducted amongst law professionals across age, gender, type and years of experience in court, to determine their understanding of DNA, fingerprints and other interdisciplinary scientific materials used as forensic evidence. In our study, we understand the levels of understanding amongst lawyers with regards to DNA and fingerprint evidence, and how it affects trial outcomes. We also aim to understand the factors that prevent credible and advanced awareness amongst legal personnel, amongst others. The survey identified the areas in modern and advanced forensics, such as forensic entomology, anthropology, cybercrime etc., in which Indian legal professionals are yet to attain a functional understanding. It also brings to light, what is commonly termed as the ‘CSI-effect’ in the Western courtrooms, and provides scope to study the existence of this phenomenon and its effects on the Indian courts and their judgements. This study highlighted the prevalence of unchallenged expert testimony presented by the prosecution in criminal trials and impressed upon the judicial system the need for independent analysis and evaluation of the scientist’s data and/or testimony by the defense. Overall, this study aims to define a clearer and rigid understanding of why legal professionals should have basic understanding of the interdisciplinary nature of forensic sciences. Based on the aforementioned findings, the author suggests various measures by which judges and lawyers might obtain an extensive knowledge of the advances and promising potentialities of forensic science. This includes promoting a forensic curriculum in legal studies at Bachelor’s and Master’s level as well as in mid-career professional courses. Formation of forensic-legal consultancies, in consultation with the Department of Justice, will not only assist in training police, military and law personnel but will also encourage legal research in this field. These suggestions also aim to bridge the communication gap that presently exists between law practitioners, forensic scientists and the general community’s awareness of the criminal justice system.Keywords: forensic science, Indian legal professionals, interdisciplinary awareness, legal education
Procedia PDF Downloads 338272 Empirical Decomposition of Time Series of Power Consumption
Authors: Noura Al Akkari, Aurélie Foucquier, Sylvain Lespinats
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Load monitoring is a management process for energy consumption towards energy savings and energy efficiency. Non Intrusive Load Monitoring (NILM) is one method of load monitoring used for disaggregation purposes. NILM is a technique for identifying individual appliances based on the analysis of the whole residence data retrieved from the main power meter of the house. Our NILM framework starts with data acquisition, followed by data preprocessing, then event detection, feature extraction, then general appliance modeling and identification at the final stage. The event detection stage is a core component of NILM process since event detection techniques lead to the extraction of appliance features. Appliance features are required for the accurate identification of the household devices. In this research work, we aim at developing a new event detection methodology with accurate load disaggregation to extract appliance features. Time-domain features extracted are used for tuning general appliance models for appliance identification and classification steps. We use unsupervised algorithms such as Dynamic Time Warping (DTW). The proposed method relies on detecting areas of operation of each residential appliance based on the power demand. Then, detecting the time at which each selected appliance changes its states. In order to fit with practical existing smart meters capabilities, we work on low sampling data with a frequency of (1/60) Hz. The data is simulated on Load Profile Generator software (LPG), which was not previously taken into consideration for NILM purposes in the literature. LPG is a numerical software that uses behaviour simulation of people inside the house to generate residential energy consumption data. The proposed event detection method targets low consumption loads that are difficult to detect. Also, it facilitates the extraction of specific features used for general appliance modeling. In addition to this, the identification process includes unsupervised techniques such as DTW. To our best knowledge, there exist few unsupervised techniques employed with low sampling data in comparison to the many supervised techniques used for such cases. We extract a power interval at which falls the operation of the selected appliance along with a time vector for the values delimiting the state transitions of the appliance. After this, appliance signatures are formed from extracted power, geometrical and statistical features. Afterwards, those formed signatures are used to tune general model types for appliances identification using unsupervised algorithms. This method is evaluated using both simulated data on LPG and real-time Reference Energy Disaggregation Dataset (REDD). For that, we compute performance metrics using confusion matrix based metrics, considering accuracy, precision, recall and error-rate. The performance analysis of our methodology is then compared with other detection techniques previously used in the literature review, such as detection techniques based on statistical variations and abrupt changes (Variance Sliding Window and Cumulative Sum).Keywords: general appliance model, non intrusive load monitoring, events detection, unsupervised techniques;
Procedia PDF Downloads 74271 Management of Hypoglycemia in Von Gierke’s Disease
Authors: Makda Aamir, Sood Aayushi, Syed Omar, Nihan Khuld, Iskander Peter, Ijaz Naeem, Sharma Nishant
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Introduction:Glycogen Storage Disease Type-1 (GSD-1) is a rare phenomenon primarily affecting the liver and kidney. Excessive accumulation of glycogen and fat in liver, kidney, and intestinal mucosa is noted in patients with deficiency of Glucose-6-phosphatase deficiency. Patients with GSD-1 have a wide spectrum of symptoms, including hepatomegaly, hypoglycemia, lactic acidemia, hyperlipidemia, hyperuricemia, and growth retardation. Age of onset, rate of disease progression and its severity is variable in this disease.Case:An 18-year-old male with GSD-1a, Von Gierke’s disease, hyperuricemia, and hypertension presented to the hospital with nausea and vomiting. The patient followed an hourly cornstarch regimen during the day and overnight through infusion via a PEG tube. The complaints started at work, where he was unable to tolerate oral cornstarch. He washemodynamically stable on arrival. ABG showed pH 7.372, PaCO2 30.3, and PaO2 92.2. WBC 16.80, K+ 5.8, HCO3 13, BUN 28, Cr 2.2, Glucose 60, AST 115, ALT 128, Cholesterol 352, Triglycerides >1000, Uric Acid 10.6, Lactic Acid 11.8 which trended down to 8.0. CT abdomen showed hepatomegaly and fatty infiltration with the PEG tube in place.He was admitted to the ICU and started on D5NS for hypoglycemia and lactic acidosis. Per request by the patient’s pediatrician, he was transitioned to IV D10/0.45NS at 110mL/Hr to maintain blood glucose above 75 mg/L. Frequent accuchecks were done till he could tolerate his dietary regimen with cornstarch. Lactic acid downtrend to 2.9, and accuchecks ranged between 100-110. Cr improved to 1.3, and his home medications (Allopurinol and Lisinopril) were resumed. He was discharged in stable condition with plans for further genetic therapy work up.Discussion:Mainstay therapy for Von Gierke’s Disease is the prevention of metabolic derangements for which dietary and lifestyle changes are recommended. A low fructose and sucrose diet is recommended by limiting the intake of galactose and lactose to one serving per day. Hypoglycemia treatment in such patients is two-fold, utilizing both quick and stable release sources. Cornstarch has been one such therapy since the 1980s; its slow digestion provides a steady release of glucose over a longer period of time as compared with other sources of carbohydrates. Dosing guidelines vary from age to age and person to person, but it is highly recommended to check BG levels frequently to maintain a BG > 70 mg/dL. Associated high levels of triglycerides and cholesterol can be treated with statins, fibrates, etc. Conclusion:The management of hypoglycemia in GSD 1 disease presents various obstacles which could prove to be fatal. Due to the deficiency of G6P, treatment with a specialized hypoglycemic regimen is warranted. A D10 ½ NS infusion can be used to maintain blood sugar levels as well as correct metabolic or lactate imbalances. Infusion should be gradually weaned off after the patient can tolerate oral feeds as this can help prevent the risk of hypoglycemia and other derangements. Further research is needed in regards to these patients for more sustainable regimens.Keywords: von gierke, glycogen storage disease, hypoglycemia, genetic disease
Procedia PDF Downloads 101270 Vortex Generation to Model the Airflow Downstream of a Piezoelectric Fan Array
Authors: Alastair Hales, Xi Jiang, Siming Zhang
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Numerical methods are used to generate vortices in a domain. Through considered design, two counter-rotating vortices may interact and effectively drive one another downstream. This phenomenon is comparable to the vortex interaction that occurs in a region immediately downstream from two counter-oscillating piezoelectric (PE) fan blades. PE fans are small blades clamped at one end and driven to oscillate at their first natural frequency by an extremely low powered actuator. In operation, the high oscillation amplitude and frequency generate sufficient blade tip speed through the surrounding air to create downstream air flow. PE fans are considered an ideal solution for low power hot spot cooling in a range of small electronic devices, but a single blade does not typically induce enough air flow to be considered a direct alternative to conventional air movers, such as axial fans. The development of face-to-face PE fan arrays containing multiple blades oscillating in counter-phase to one another is essential for expanding the range of potential PE fan applications regarding the cooling of power electronics. Even in an unoptimised state, these arrays are capable of moving air volumes comparable to axial fans with less than 50% of the power demand. Replicating the airflow generated by face-to-face PE fan arrays without including the actual blades in the model reduces the process’s computational demands and enhances the rate of innovation and development in the field. Vortices are generated at a defined inlet using a time-dependent velocity profile function, which pulsates the inlet air velocity magnitude. This induces vortex generation in the considered domain, and these vortices are shown to separate and propagate downstream in a regular manner. The generation and propagation of a single vortex are compared to an equivalent vortex generated from a PE fan blade in a previous experimental investigation. Vortex separation is found to be accurately replicated in the present numerical model. Additionally, the downstream trajectory of the vortices’ centres vary by just 10.5%, and size and strength of the vortices differ by a maximum of 10.6%. Through non-dimensionalisation, the numerical method is shown to be valid for PE fan blades with differing parameters to the specific case investigated. The thorough validation methods presented verify that the numerical model may be used to replicate vortex formation from an oscillating PE fans blade. An investigation is carried out to evaluate the effects of varying the distance between two PE fan blade, pitch. At small pitch, the vorticity in the domain is maximised, along with turbulence in the near vicinity of the inlet zones. It is proposed that face-to-face PE fan arrays, oscillating in counter-phase, should have a minimal pitch to optimally cool nearby heat sources. On the other hand, downstream airflow is maximised at a larger pitch, where the vortices can fully form and effectively drive one another downstream. As such, this should be implemented when bulk airflow generation is the desired result.Keywords: piezoelectric fans, low energy cooling, vortex formation, computational fluid dynamics
Procedia PDF Downloads 174269 Synergistic Studies of Liposomes of Clove and Cinnamon Oil in Oral Health Care
Authors: Sandhya Parameswaran, Prajakta Dhuri
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Despite great improvements in health care, the world oral health report states that dental problems still persist, particularly among underprivileged groups in both developing and developed countries. Dental caries and periodontal diseases are identified as the most important oral health problems globally. Acidic foods and beverages can affect natural teeth, and chronic exposure often leads to the development of dental erosion, abrasion, and decay. In recent years, there has been an increased interest toward essential oils. These are secondary metabolites and possess antibacterial, antifungal and antioxidant properties. Essential oils are volatile and chemically unstable in the presence of air, light, moisture and high temperature. Hence many novel methods like a liposomal encapsulation of oils have been introduced to enhance the stability and bioavailability. This research paper focuses on two essential oils, clove and cinnamon oil. Clove oil was obtained from Syzygium aromaticum Linn using clavengers apparatus. It contains eugenol and β caryophyllene. Cinnamon oil, from the barks of Cinnamomum cassia, contains cinnamaldehyde, The objective of the current research was to develop a liposomal carrier system containing clove and cinnamon oil and study their synergistic activity against dental pathogens when formulated as a gel. Methodology: The essential oil were first tested for their antimicrobial activity against dental pathogens, Lactobacillus acidophillus (MTCC No. 10307, MRS broth) and Streptococcus Mutans (MTCC No .890, Brain Heart Infusion agar). The oils were analysed by UV spectroscopy for eugenol and cinnamaldehyde content. Standard eugenol was linear between 5ppm to 25ppm at 282nm and standard cinnamaldehde from 1ppm to 5pmm at 284nm. The concentration of eugenol in clove oil was found to be 62.65 % w/w, and that of cinnamaldehyde was found to be 5.15%s w/w. The oils were then formulated into liposomes. Liposomes were prepared by thin film hydration method using Phospholipid, Cholesterol, and other oils dissolved in a chloroform methanol (3:1) mixture. The organic solvent was evaporated in a rotary evaporator above lipid transition temperature. The film was hydrated with phosphate buffer (pH 5.5).The various batches of liposomes were characterized and compared for their size, loading rate, encapsulation efficiency and morphology. The prepared liposomes when evaluated for entrapment efficiency showed 65% entrapment for clove and 85% for cinnamon oil. They were also tested for their antimicrobial activity against dental pathogens and their synergistic activity studied. Based on the activity and the entrapment efficiency the amount of liposomes required to prepare 1gm of the gel was calculated. The gel was prepared using a simple ointment base and contained 0.56% of cinnamon and clove liposomes. A simultaneous method of analysis for eugenol and cinnamaldehyde.was then developed using HPLC. The prepared gels were then studied for their stability as per ICH guidelines. Conclusion: It was found that liposomes exhibited spherical shaped vesicles and protected the essential oil from degradation. Liposomes, therefore, constitute a suitable system for encapsulation of volatile, unstable essential oil constituents.Keywords: cinnamon oil, clove oil, dental caries, liposomes
Procedia PDF Downloads 188268 Isolation and Characterization of a Narrow-Host Range Aeromonas hydrophila Lytic Bacteriophage
Authors: Sumeet Rai, Anuj Tyagi, B. T. Naveen Kumar, Shubhkaramjeet Kaur, Niraj K. Singh
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Since their discovery, indiscriminate use of antibiotics in human, veterinary and aquaculture systems has resulted in global emergence/spread of multidrug-resistant bacterial pathogens. Thus, the need for alternative approaches to control bacterial infections has become utmost important. High selectivity/specificity of bacteriophages (phages) permits the targeting of specific bacteria without affecting the desirable flora. In this study, a lytic phage (Ahp1) specific to Aeromonas hydrophila subsp. hydrophila was isolated from finfish aquaculture pond. The host range of Ahp1 range was tested against 10 isolates of A. hydrophila, 7 isolates of A. veronii, 25 Vibrio cholerae isolates, 4 V. parahaemolyticus isolates and one isolate each of V. harveyi and Salmonella enterica collected previously. Except the host A. hydrophila subsp. hydrophila strain, no lytic activity against any other bacterial was detected. During the adsorption rate and one-step growth curve analysis, 69.7% of phage particles were able to get adsorbed on host cell followed by the release of 93 ± 6 phage progenies per host cell after a latent period of ~30 min. Phage nucleic acid was extracted by column purification methods. After determining the nature of phage nucleic acid as dsDNA, phage genome was subjected to next-generation sequencing by generating paired-end (PE, 2 x 300bp) reads on Illumina MiSeq system. De novo assembly of sequencing reads generated circular phage genome of 42,439 bp with G+C content of 58.95%. During open read frame (ORF) prediction and annotation, 22 ORFs (out of 49 total predicted ORFs) were functionally annotated and rest encoded for hypothetical proteins. Proteins involved in major functions such as phage structure formation and packaging, DNA replication and repair, DNA transcription and host cell lysis were encoded by the phage genome. The complete genome sequence of Ahp1 along with gene annotation was submitted to NCBI GenBank (accession number MF683623). Stability of Ahp1 preparations at storage temperatures of 4 °C, 30 °C, and 40 °C was studied over a period of 9 months. At 40 °C storage, phage counts declined by 4 log units within one month; with a total loss of viability after 2 months. At 30 °C temperature, phage preparation was stable for < 5 months. On the other hand, phage counts decreased by only 2 log units over a period of 9 during storage at 4 °C. As some of the phages have also been reported as glycerol sensitive, the stability of Ahp1 preparations in (0%, 15%, 30% and 45%) glycerol stocks were also studied during storage at -80 °C over a period of 9 months. The phage counts decreased only by 2 log units during storage, and no significant difference in phage counts was observed at different concentrations of glycerol. The Ahp1 phage discovered in our study had a very narrow host range and it may be useful for phage typing applications. Moreover, the endolysin and holin genes in Ahp1 genome could be ideal candidates for recombinant cloning and expression of antimicrobial proteins.Keywords: Aeromonas hydrophila, endolysin, phage, narrow host range
Procedia PDF Downloads 160267 Predicting Food Waste and Losses Reduction for Fresh Products in Modified Atmosphere Packaging
Authors: Matar Celine, Gaucel Sebastien, Gontard Nathalie, Guilbert Stephane, Guillard Valerie
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To increase the very short shelf life of fresh fruits and vegetable, Modified Atmosphere Packaging (MAP) allows an optimal atmosphere composition to be maintained around the product and thus prevent its decay. This technology relies on the modification of internal packaging atmosphere due to equilibrium between production/consumption of gases by the respiring product and gas permeation through the packaging material. While, to the best of our knowledge, benefit of MAP for fresh fruits and vegetable has been widely demonstrated in the literature, its effect on shelf life increase has never been quantified and formalized in a clear and simple manner leading difficult to anticipate its economic and environmental benefit, notably through the decrease of food losses. Mathematical modelling of mass transfers in the food/packaging system is the basis for a better design and dimensioning of the food packaging system. But up to now, existing models did not permit to estimate food quality nor shelf life gain reached by using MAP. However, shelf life prediction is an indispensable prerequisite for quantifying the effect of MAP on food losses reduction. The objective of this work is to propose an innovative approach to predict shelf life of MAP food product and then to link it to a reduction of food losses and wastes. In this purpose, a ‘Virtual MAP modeling tool’ was developed by coupling a new predictive deterioration model (based on visual surface prediction of deterioration encompassing colour, texture and spoilage development) with models of the literature for respiration and permeation. A major input of this modelling tool is the maximal percentage of deterioration (MAD) which was assessed from dedicated consumers’ studies. Strawberries of the variety Charlotte were selected as the model food for its high perishability, high respiration rate; 50-100 ml CO₂/h/kg produced at 20°C, allowing it to be a good representative of challenging post-harvest storage. A value of 13% was determined as a limit of acceptability for the consumers, permitting to define products’ shelf life. The ‘Virtual MAP modeling tool’ was validated in isothermal conditions (5, 10 and 20°C) and in dynamic temperature conditions mimicking commercial post-harvest storage of strawberries. RMSE values were systematically lower than 3% for respectively, O₂, CO₂ and deterioration profiles as a function of time confirming the goodness of model fitting. For the investigated temperature profile, a shelf life gain of 0.33 days was obtained in MAP compared to the conventional storage situation (no MAP condition). Shelf life gain of more than 1 day could be obtained for optimized post-harvest conditions as numerically investigated. Such shelf life gain permitted to anticipate a significant reduction of food losses at the distribution and consumer steps. This food losses' reduction as a function of shelf life gain has been quantified using a dedicated mathematical equation that has been developed for this purpose.Keywords: food losses and wastes, modified atmosphere packaging, mathematical modeling, shelf life prediction
Procedia PDF Downloads 180266 A Hybrid of BioWin and Computational Fluid Dynamics Based Modeling of Biological Wastewater Treatment Plants for Model-Based Control
Authors: Komal Rathore, Kiesha Pierre, Kyle Cogswell, Aaron Driscoll, Andres Tejada Martinez, Gita Iranipour, Luke Mulford, Aydin Sunol
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Modeling of Biological Wastewater Treatment Plants requires several parameters for kinetic rate expressions, thermo-physical properties, and hydrodynamic behavior. The kinetics and associated mechanisms become complex due to several biological processes taking place in wastewater treatment plants at varying times and spatial scales. A dynamic process model that incorporated the complex model for activated sludge kinetics was developed using the BioWin software platform for an Advanced Wastewater Treatment Plant in Valrico, Florida. Due to the extensive number of tunable parameters, an experimental design was employed for judicious selection of the most influential parameter sets and their bounds. The model was tuned using both the influent and effluent plant data to reconcile and rectify the forecasted results from the BioWin Model. Amount of mixed liquor suspended solids in the oxidation ditch, aeration rates and recycle rates were adjusted accordingly. The experimental analysis and plant SCADA data were used to predict influent wastewater rates and composition profiles as a function of time for extended periods. The lumped dynamic model development process was coupled with Computational Fluid Dynamics (CFD) modeling of the key units such as oxidation ditches in the plant. Several CFD models that incorporate the nitrification-denitrification kinetics, as well as, hydrodynamics was developed and being tested using ANSYS Fluent software platform. These realistic and verified models developed using BioWin and ANSYS were used to plan beforehand the operating policies and control strategies for the biological wastewater plant accordingly that further allows regulatory compliance at minimum operational cost. These models, with a little bit of tuning, can be used for other biological wastewater treatment plants as well. The BioWin model mimics the existing performance of the Valrico Plant which allowed the operators and engineers to predict effluent behavior and take control actions to meet the discharge limits of the plant. Also, with the help of this model, we were able to find out the key kinetic and stoichiometric parameters which are significantly more important for modeling of biological wastewater treatment plants. One of the other important findings from this model were the effects of mixed liquor suspended solids and recycle ratios on the effluent concentration of various parameters such as total nitrogen, ammonia, nitrate, nitrite, etc. The ANSYS model allowed the abstraction of information such as the formation of dead zones increases through the length of the oxidation ditches as compared to near the aerators. These profiles were also very useful in studying the behavior of mixing patterns, effect of aerator speed, and use of baffles which in turn helps in optimizing the plant performance.Keywords: computational fluid dynamics, flow-sheet simulation, kinetic modeling, process dynamics
Procedia PDF Downloads 202265 Employee Commitment as a Means of Revitalising the Hospitality Industry post-Covid: Considering the Impact of Psychological Contract and Psychological Capital
Authors: Desere Kokt
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Hospitality establishments worldwide are bearing the brunt of the effects of Covid-19. As the hospitality industry is looking to recover, emphasis is placed on rejuvenating the industry. This is especially pertinent for economic development in areas of high unemployment, such as the Free State province of South Africa. The province is not a main tourist area and thus depends on the influx of tourists. The province has great scenic beauty with many accommodation establishments that provide job opportunities to the local population. The two main economic hubs of the Free State province namely Bloemfontein and Clarens, were the focus of the investigation. The emphasis was on graded accommodation establishments as they must adhere to the quality principles of the Tourism Grading Council of South Africa (TGCSA) to obtain star grading. The hospitality industry is known for being labour intensive, and employees need to be available to cater for the needs of paying customers. This is referred to as ‘emotional labour’ and implies that employees need to manage their feelings and emotions as part of performing their jobs. The focus of this study was thus on psychological factors related to working in the hospitality industry – specifically psychological contract and psychological capital and its impact on the commitment of employees in graded accommodation establishments. Employee commitment can be explained as a psychological state that binds the individual to the organisation and involves a set of psychological relationships that include affective (emotions), normative (perceived obligation) and continuance (staying with the organisation) dimensions. Psychological contract refers to the reciprocal beliefs and expectations between the employer and the employee and consists of transactional and rational contracts. Transactional contracts are associated with the economic exchange, and contractional issues related to the employment contract and rational contracts relate to the social exchange between the employee and the organisation. Psychological capital refers to an individual’s positive psychology state of development that is characterised by self-efficiency (having confidence in doing one’s job), optimism (being positive and persevering towards achieving one’s goals), hope (expectations for goals to succeed) and resilience (bouncing back to attain success when beset by problems and adversity). The study employed a quantitative research approach, and a structured questionnaire was used to gather data from respondents. The study was conducted during the Covid-19 pandemic, which hampered the data gathering efforts of the researchers. Many accommodation establishments were either closed or temporarily closed, which meant that data gathering was an intensive and laborious process. The main researcher travelled to the various establishments to collect the data. Nine hospitality establishments participated in the study, and around 150 employees were targeted for data collection. Ninety-two (92) questionnaires were completed, which represents a response rate of 61%. Data were analysed using descriptive and inferential statistics, and partial least squares structural equation modelling (PLS-SEM) was applied to examine the relationship between the variables.Keywords: employee commitment, hospitality industry, psychological contract, psychological capital
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