Search results for: SCM and the environmental impact
1158 Pioneering Conservation of Aquatic Ecosystems under Australian Law
Authors: Gina M. Newton
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Australia’s Environment Protection and Biodiversity Conservation Act (EPBC Act) is the premiere, national law under which species and 'ecological communities' (i.e., like ecosystems) can be formally recognised and 'listed' as threatened across all jurisdictions. The listing process involves assessment against a range of criteria (similar to the IUCN process) to demonstrate conservation status (i.e., vulnerable, endangered, critically endangered, etc.) based on the best available science. Over the past decade in Australia, there’s been a transition from almost solely terrestrial to the first aquatic threatened ecological community (TEC or ecosystem) listings (e.g., River Murray, Macquarie Marshes, Coastal Saltmarsh, Salt-wedge Estuaries). All constitute large areas, with some including multiple state jurisdictions. Development of these conservation and listing advices has enabled, for the first time, a more forensic analysis of three key factors across a range of aquatic and coastal ecosystems: -the contribution of invasive species to conservation status, -how to demonstrate and attribute decline in 'ecological integrity' to conservation status, and, -identification of related priority conservation actions for management. There is increasing global recognition of the disproportionate degree of biodiversity loss within aquatic ecosystems. In Australia, legislative protection at Commonwealth or State levels remains one of the strongest conservation measures. Such laws have associated compliance mechanisms for breaches to the protected status. They also trigger the need for environment impact statements during applications for major developments (which may be denied). However, not all jurisdictions have such laws in place. There remains much opposition to the listing of freshwater systems – for example, the River Murray (Australia's largest river) and Macquarie Marshes (an internationally significant wetland) were both disallowed by parliament four months after formal listing. This was mainly due to a change of government, dissent from a major industry sector, and a 'loophole' in the law. In Australia, at least in the immediate to medium-term time frames, invasive species (aliens, native pests, pathogens, etc.) appear to be the number one biotic threat to the biodiversity and ecological function and integrity of our aquatic ecosystems. Consequently, this should be considered a current priority for research, conservation, and management actions. Another key outcome from this analysis was the recognition that drawing together multiple lines of evidence to form a 'conservation narrative' is a more useful approach to assigning conservation status. This also helps to addresses a glaring gap in long-term ecological data sets in Australia, which often precludes a more empirical data-driven approach. An important lesson also emerged – the recognition that while conservation must be underpinned by the best available scientific evidence, it remains a 'social and policy' goal rather than a 'scientific' goal. Communication, engagement, and 'politics' necessarily play a significant role in achieving conservation goals and need to be managed and resourced accordingly.Keywords: aquatic ecosystem conservation, conservation law, ecological integrity, invasive species
Procedia PDF Downloads 1321157 Palaeo-Environmental Reconstruction of the Wet Zone of Sri Lanka: A Zooarchaeological Perspective
Authors: Kalangi Rodrigo
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Sri Lanka has been known as an island which has a diverse variety of prehistoric occupation among ecological zones. Defining the paleoecology of the past societies has been an archaeological thought developed in the 1960s. It is mainly concerned with the reconstruction from available geological and biological evidence of past biota, populations, communities, landscapes, environments, and ecosystems. Sri Lanka has dealt with this subject, and considerable research has been already undertaken. The fossil and material record of Sri Lanka’s Wet Zone tropical forests continues from c. 38,000–34,000 ybp. This early and persistent human fossil, technical, and cultural florescence, as well as a collection of well-preserved tropical-forest rock shelters with associated 'on-site' palaeoenvironmental records, makes Sri Lanka a central and unusual case study to determine the extent and strength of early human tropical forest encounters. Excavations carried out in prehistoric caves in the low country wet zone has shown that in the last 50,000 years, the temperature in the lowland rainforests has not exceeded 5°C. When taking Batadombalena alone, the entire seven layers have yielded an uninterrupted occupation of Acavus sp and Canerium zeylanicum, a plant that grows in the middle of the rainforest. Acavus, which is highly sensitive to rainforest ecosystems, has been well documented in many of the lowland caves, confirming that the wetland rainforest environment has remained intact at least for the last 50,000 years. If the dry and arid conditions in the upper hills regions affected the wet zone, the Tufted Gray Lunger (semnopithecus priam), must also meet with the prehistoric caves in the wet zone thrown over dry climate. However, the bones in the low country wet zone do not find any of the fragments belonging to Turfed Gray Lunger, and prehistoric human consumption is bestowed with purple-faced leaf monkey (Trachypithecus vetulus) and Toque Macaque (Macaca Sinica). The skeletal remains of Lyriocephalus scutatus, a full-time resident in rain forests, have also been recorded among lowland caves. But, in zoological terms, these remains may be the remains of the Barking deer (Muntiacus muntjak), which is currently found in the wet zone. For further investigations, the mtDNA test of genetic diversity (Bottleneck effect) and pollen study from lowland caves should determine whether the wet zone climate has persisted over the last 50,000 years, or whether the dry weather affected in the mountainous region has invaded the wet zone.Keywords: paleoecology, prehistory, zooarchaeology, reconstruction, palaeo-climate
Procedia PDF Downloads 1401156 Temporal Estimation of Hydrodynamic Parameter Variability in Constructed Wetlands
Authors: Mohammad Moezzibadi, Isabelle Charpentier, Adrien Wanko, Robert Mosé
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The calibration of hydrodynamic parameters for subsurface constructed wetlands (CWs) is a sensitive process since highly non-linear equations are involved in unsaturated flow modeling. CW systems are engineered systems designed to favour natural treatment processes involving wetland vegetation, soil, and their microbial flora. Their significant efficiency at reducing the ecological impact of urban runoff has been recently proved in the field. Numerical flow modeling in a vertical variably saturated CW is here carried out by implementing the Richards model by means of a mixed hybrid finite element method (MHFEM), particularly well adapted to the simulation of heterogeneous media, and the van Genuchten-Mualem parametrization. For validation purposes, MHFEM results were compared to those of HYDRUS (a software based on a finite element discretization). As van Genuchten-Mualem soil hydrodynamic parameters depend on water content, their estimation is subject to considerable experimental and numerical studies. In particular, the sensitivity analysis performed with respect to the van Genuchten-Mualem parameters reveals a predominant influence of the shape parameters α, n and the saturated conductivity of the filter on the piezometric heads, during saturation and desaturation. Modeling issues arise when the soil reaches oven-dry conditions. A particular attention should also be brought to boundary condition modeling (surface ponding or evaporation) to be able to tackle different sequences of rainfall-runoff events. For proper parameter identification, large field datasets would be needed. As these are usually not available, notably due to the randomness of the storm events, we thus propose a simple, robust and low-cost numerical method for the inverse modeling of the soil hydrodynamic properties. Among the methods, the variational data assimilation technique introduced by Le Dimet and Talagrand is applied. To that end, a variational data assimilation technique is implemented by applying automatic differentiation (AD) to augment computer codes with derivative computations. Note that very little effort is needed to obtain the differentiated code using the on-line Tapenade AD engine. Field data are collected for a three-layered CW located in Strasbourg (Alsace, France) at the water edge of the urban water stream Ostwaldergraben, during several months. Identification experiments are conducted by comparing measured and computed piezometric head by means of the least square objective function. The temporal variability of hydrodynamic parameter is then assessed and analyzed.Keywords: automatic differentiation, constructed wetland, inverse method, mixed hybrid FEM, sensitivity analysis
Procedia PDF Downloads 1641155 Alcohol and Soda Consumption of University Students in Manila
Authors: Alexi Colleen F. Lim, Inna Felicia I. Agoncillo, Quenniejoy T. Dizon, Jennifer Joyce T. Eti, Carlota Aileen H. Monares, Neil Roy B. Rosales, Joshua F. Santillan, Alyssa Francesca D. S. Tanchuling, Josefina A. Tuazon, Mary Joan Therese C. Valera-Kourdache
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Majority of leading causes of mortality in the Philippines are NCDs, which are preventable through control of known risk factors such as smoking, obesity, physical inactivity, and alcohol. Sugar-sweetened beverages such as soda and energy drinks also contribute to NCD risk and are of concern particularly for youth. This study provides baseline data on beverage consumption of university students in Manila with the focus on alcohol and soda. It further aims to identify factors affecting consumption. Specific objectives include: (1) to describe beverage consumption practices of university students in Manila; and (2) to determine factors promoting excessive consumption of alcohol and soda including demographic characteristics, attitude, interpersonal and environmental variables. Methods: The study employed correlational design with randomly selected students from two universities in Manila. Students 18 years or older who agreed to participate were included after obtaining ethical clearance. The study had two instruments: (1) World Health Organization’s Alcohol Use Disorders Identification Test (AUDIT) was used with permission, to determine excessive alcohol consumption; and (2) a questionnaire to obtain information regarding soda and energy drink consumption. Results: Out of 400 students surveyed, 70% were female and 78.75% were 18-20 years old (mean=19.79; SD=3.76). Among them, 51.50% consumed alcohol, with 30.10% excessive drinkers. Soda consumption is 91.50% with 37.70% excessive consumers. For energy drinks, 36.75% consume this and only 4.76% drink excessively. Using logistic regression, students who were more likely to be excessive alcohol drinkers belonged to non-health courses (OR=2.21) and purchased alcohol from bars (OR=7.84). Less likely to drink excessively are students who do not drink due to stress (OR=0.05) and drink when it is accessible (OR=0.02). Excessive soda consumption was less likely for female students (OR=0.28), those who drink when it is accessible (OR=0.14), do not drink soda during stressful situations (OR=0.19), and do not use soda as hangover treatment (OR=0.15). Conclusion: Excessive alcohol consumption was greater among students in Manila (30.10%) than in US (20%). Drinking alcohol with friends was not related to excessive consumption but availability in bars was. It is expected that health sciences students are less likely to engage in excessive alcohol as they are more aware of its ill effects. Prevalence of soda consumption in Manila (91.50%) is markedly higher compared to 24.5% in the US. These findings can inform schools in developing appropriate health education interventions and policies. For greater understanding of these behaviors and factors, further studies are recommended to explore knowledge and other factors that may promote excessive consumption.Keywords: alcohol consumption, beverage consumption, energy drinks consumption, soda consumption, university students
Procedia PDF Downloads 2791154 Are Oral Health Conditions Associated with Children’s School Performance and School Attendance in the Kingdom of Bahrain - A Life Course Approach
Authors: Seham A. S. Mohamed, Sarah R. Baker, Christopher Deery, Mario V. Vettore
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Background: The link between oral health conditions and school performance and attendance remain unclear among Middle Eastern children. The association has been studied extensively in the Western region; however, several concerns have been raised regarding the reliability and validity of measures, low quality of studies, inadequate inclusion of potential confounders, and the lack of a conceptual framework. These limitations have meant that, to date, there has been no detailed understanding of the association or of the key social, clinical, behavioural and parental factors which may impact the association. Aim: To examine the association between oral health conditions and children’s school performance and attendance at Grade 2 in Muharraq city in the Kingdom of Bahrain using Heilmann et al.’s (2015) life course framework for oral health. Objectives: To (1) describe the prevalence of oral health conditions among 7-8 years old schoolchildren in the city of Muharraq; (2) analyse the social, biological, behavioural, and parental pathways that link early and current life exposures with children’s current oral health status; (3) examine the association between oral health conditions and school performance and attendance among schoolchildren; (4) explore the early and current life course social, biological, behavioural and parental factors associated with children’s school outcomes. Design: A time-ordered-cross-sectional study was conducted with 466 schoolchildren aged 7-8 years and their parents from Muharraq city in KoB. Data were collected through parents’ self-administered questionnaires, children’s face-face interviews, and dental clinical examinations. Outcome variables, including school performance and school attendance data, were obtained from the parents and school records. The data were analysed using structural equation modelling (SEM). Results: Dental caries, the consequence of dental caries (PUFA/pufa), and enamel developmental defects (EDD) prevalence were 93.4%, 25.7%, and 17.2%, respectively. The findings from the SEM showed that children born in families with high SES were less likely to suffer from dentine dental caries (β= -0.248) and more likely to earn high school performance (β= 0.136) at 7-8 years of age in Muharraq. From the current life course of children, the dental plaque was associated significantly and directly with enamel caries (β= 0.094), dentine caries (β= 0.364), treated teeth (filled or extracted because of dental caries) (β= 0.121), and indirectly associated with dental pain (β= 0.057). Further, dentine dental caries was associated significantly and directly with low school performance (β= -0.155). At the same time, the dental plaque was indirectly associated with low school performance via dental caries (β = −0.044). Conversely, treated teeth were associated directly with high school performance (β= 0.100). Notably, none of the OHCs, biological, SES, behavioural, or parental conditions was related to school attendance in children. Conclusion: The life course approach was adequate to examine the role of OHCs on children’s school performance and attendance. Birth and current (7-8-year-olds) social factors were significant predictors of poor OH and poor school performance.Keywords: dental caries, life course, Bahrain, school outcomes
Procedia PDF Downloads 1071153 Elaboration and Characterization of in-situ CrC- Ni(Al, Cr) Composites Elaborated from Ni and Cr₂AlC Precursors
Authors: A. Chiker, A. Benamor, A. Haddad, Y. Hadji, M. Hadji
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Metal matrix composites (MMCs) have been of big interest for a few decades. Their major drawback lies in their enhanced mechanical performance over unreinforced alloys. They found ground in many engineering fields, such as aeronautics, aerospace, automotive, and other structural applications. One of the most used alloys as a matrix is nickel alloys, which meet the need for high-temperature mechanical properties; some attempts have been made to develop nickel base composites reinforced by high melt point and high modulus particulates. Among the carbides used as reinforcing particulates, chromium carbide is interesting for wear applications; it is widely used as a tribological coating material in high-temperature applications requiring high wear resistance and hardness. Moreover, a set of properties make it suitable for use in MMCs, such as toughness, the good corrosion and oxidation resistance of its three polymorphs -the cubic (Cr23C6), the hexagonal (Cr7C3), and the orthorhombic (Cr3C2)-, and it’s coefficient of thermal expansion that is almost equal to that of metals. The in-situ synthesis of CrC-reinforced Ni matrix composites could be achieved by the powder metallurgy route. To ensure the in-situ reactions during the sintering process, the use of phase precursors is necessary. Recently, new precursor materials have been proposed; these materials are called MAX phases. The MAX phases are thermodynamically stable nano-laminated materials displaying unusual and sometimes unique properties. These novel phases possess Mn+1AXn chemistry, where n is 1, 2, or 3, M is an early transition metal element, A is an A-group element, and X is C or N. Herein, the pressureless sintering method is used to elaborate Ni/Cr2AlC composites. Four composites were elaborated from 5, 10, 15 and 20 wt% of Cr2AlC MAX phase precursor which fully reacted with Ni-matrix at 1100 °C sintering temperature for 4 h in argon atmosphere. XRD results showed that Cr2AlC MAX phase was totally decomposed forming chromium carbide Cr7C3, and the released Al and Cr atoms diffused in Ni matrix giving rise to γ-Ni(Al,Cr) solid solution and γ’-Ni3(Al,Cr) intermetallic. Scanning Electron Microscopy (SEM) of the elaborated samples showed the presence of nanosized Cr7C3 reinforcing particles embedded in the Ni metal matrix, which have a direct impact on the tribological properties of the composites and their hardness. All the composites exhibited higher hardness than pure Ni; whereas adding 15 wt% of Cr2AlC gives the highest hardness (1.85 GPa). Using a ball-on-disc tribometer, dry sliding tests for the elaborated composites against 100Cr6 steel ball were studied under different applied loads. The microstructures and worn surface characteristics were then analyzed using SEM and Raman spectroscopy. The results show that all the composites exhibited better wear resistance compared to pure Ni, which could be explained by the formation of a lubricious tribo-layer during sliding and the good bonding between the Ni matrix and the reinforcing phases.Keywords: composites, microscopy, sintering, wear
Procedia PDF Downloads 701152 Further Development of Offshore Floating Solar and Its Design Requirements
Authors: Madjid Karimirad
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Floating solar was not very well-known in the renewable energy field a decade ago; however, there has been tremendous growth internationally with a Compound Annual Growth Rate (CAGR) of nearly 30% in recent years. To reach the goal of global net-zero emission by 2050, all renewable energy sources including solar should be used. Considering that 40% of the world’s population lives within 100 kilometres of the coasts, floating solar in coastal waters is an obvious energy solution. However, this requires more robust floating solar solutions. This paper tries to enlighten the fundamental requirements in the design of floating solar for offshore installations from the hydrodynamic and offshore engineering points of view. In this regard, a closer look at dynamic characteristics, stochastic behaviour and nonlinear phenomena appearing in this kind of structure is a major focus of the current article. Floating solar structures are alternative and very attractive green energy installations with (a) Less strain on land usage for densely populated areas; (b) Natural cooling effect with efficiency gain; and (c) Increased irradiance from the reflectivity of water. Also, floating solar in conjunction with the hydroelectric plants can optimise energy efficiency and improve system reliability. The co-locating of floating solar units with other types such as offshore wind, wave energy, tidal turbines as well as aquaculture (fish farming) can result in better ocean space usage and increase the synergies. Floating solar technology has seen considerable developments in installed capacities in the past decade. Development of design standards and codes of practice for floating solar technologies deployed on both inland water-bodies and offshore is required to ensure robust and reliable systems that do not have detrimental impacts on the hosting water body. Floating solar will account for 17% of all PV energy produced worldwide by 2030. To enhance the development, further research in this area is needed. This paper aims to discuss the main critical design aspects in light of the load and load effects that the floating solar platforms are subjected to. The key considerations in hydrodynamics, aerodynamics and simultaneous effects from the wind and wave load actions will be discussed. The link of dynamic nonlinear loading, limit states and design space considering the environmental conditions is set to enable a better understanding of the design requirements of fast-evolving floating solar technology.Keywords: floating solar, offshore renewable energy, wind and wave loading, design space
Procedia PDF Downloads 791151 Application of the State of the Art of Hydraulic Models to Manage Coastal Problems, Case Study: The Egyptian Mediterranean Coast Model
Authors: Al. I. Diwedar, Moheb Iskander, Mohamed Yossef, Ahmed ElKut, Noha Fouad, Radwa Fathy, Mustafa M. Almaghraby, Amira Samir, Ahmed Romya, Nourhan Hassan, Asmaa Abo Zed, Bas Reijmerink, Julien Groenenboom
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Coastal problems are stressing the coastal environment due to its complexity. The dynamic interaction between the sea and the land results in serious problems that threaten coastal areas worldwide, in addition to human interventions and activities. This makes the coastal environment highly vulnerable to natural processes like flooding, erosion, and the impact of human activities as pollution. Protecting and preserving this vulnerable coastal zone with its valuable ecosystems calls for addressing the coastal problems. This, in the end, will support the sustainability of the coastal communities and maintain the current and future generations. Consequently applying suitable management strategies and sustainable development that consider the unique characteristics of the coastal system is a must. The coastal management philosophy aims to solve the conflicts of interest between human development activities and this dynamic nature. Modeling emerges as a successful tool that provides support to decision-makers, engineers, and researchers for better management practices. Modeling tools proved that it is accurate and reliable in prediction. With its capability to integrate data from various sources such as bathymetric surveys, satellite images, and meteorological data, it offers the possibility for engineers and scientists to understand this complex dynamic system and get in-depth into the interaction between both the natural and human-induced factors. This enables decision-makers to make informed choices and develop effective strategies for sustainable development and risk mitigation of the coastal zone. The application of modeling tools supports the evaluation of various scenarios by affording the possibility to simulate and forecast different coastal processes from the hydrodynamic and wave actions and the resulting flooding and erosion. The state-of-the-art application of modeling tools in coastal management allows for better understanding and predicting coastal processes, optimizing infrastructure planning and design, supporting ecosystem-based approaches, assessing climate change impacts, managing hazards, and finally facilitating stakeholder engagement. This paper emphasizes the role of hydraulic models in enhancing the management of coastal problems by discussing the diverse applications of modeling in coastal management. It highlights the modelling role in understanding complex coastal processes, and predicting outcomes. The importance of informing decision-makers with modeling results which gives technical and scientific support to achieve sustainable coastal development and protection.Keywords: coastal problems, coastal management, hydraulic model, numerical model, physical model
Procedia PDF Downloads 291150 Treatment and Diagnostic Imaging Methods of Fetal Heart Function in Radiology
Authors: Mahdi Farajzadeh Ajirlou
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Prior evidence of normal cardiac anatomy is desirable to relieve the anxiety of cases with a family history of congenital heart disease or to offer the option of early gestation termination or close follow-up should a cardiac anomaly be proved. Fetal heart discovery plays an important part in the opinion of the fetus, and it can reflect the fetal heart function of the fetus, which is regulated by the central nervous system. Acquisition of ventricular volume and inflow data would be useful to quantify more valve regurgitation and ventricular function to determine the degree of cardiovascular concession in fetal conditions at threat for hydrops fetalis. This study discusses imaging the fetal heart with transvaginal ultrasound, Doppler ultrasound, three-dimensional ultrasound (3DUS) and four-dimensional (4D) ultrasound, spatiotemporal image correlation (STIC), glamorous resonance imaging and cardiac catheterization. Doppler ultrasound (DUS) image is a kind of real- time image with a better imaging effect on blood vessels and soft tissues. DUS imaging can observe the shape of the fetus, but it cannot show whether the fetus is hypoxic or distressed. Spatiotemporal image correlation (STIC) enables the acquisition of a volume of data concomitant with the beating heart. The automated volume accession is made possible by the array in the transducer performing a slow single reach, recording a single 3D data set conforming to numerous 2D frames one behind the other. The volume accession can be done in a stationary 3D, either online 4D (direct volume scan, live 3D ultrasound or a so-called 4D (3D/ 4D)), or either spatiotemporal image correlation-STIC (off-line 4D, which is a circular volume check-up). Fetal cardiovascular MRI would appear to be an ideal approach to the noninvasive disquisition of the impact of abnormal cardiovascular hemodynamics on antenatal brain growth and development. Still, there are practical limitations to the use of conventional MRI for fetal cardiovascular assessment, including the small size and high heart rate of the mortal fetus, the lack of conventional cardiac gating styles to attend data accession, and the implicit corruption of MRI data due to motherly respiration and unpredictable fetal movements. Fetal cardiac MRI has the implicit to complement ultrasound in detecting cardiovascular deformations and extracardiac lesions. Fetal cardiac intervention (FCI), minimally invasive catheter interventions, is a new and evolving fashion that allows for in-utero treatment of a subset of severe forms of congenital heart deficiency. In special cases, it may be possible to modify the natural history of congenital heart disorders. It's entirely possible that future generations will ‘repair’ congenital heart deficiency in utero using nanotechnologies or remote computer-guided micro-robots that work in the cellular layer.Keywords: fetal, cardiac MRI, ultrasound, 3D, 4D, heart disease, invasive, noninvasive, catheter
Procedia PDF Downloads 401149 Monocoque Systems: The Reuniting of Divergent Agencies for Wood Construction
Authors: Bruce Wrightsman
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Construction and design are inexorably linked. Traditional building methodologies, including those using wood, comprise a series of material layers differentiated and separated from each other. This results in the separation of two agencies of building envelope (skin) separate from the structure. However, from a material performance position reliant on additional materials, this is not an efficient strategy for the building. The merits of traditional platform framing are well known. However, its enormous effectiveness within wood-framed construction has seldom led to serious questioning and challenges in defining what it means to build. There are several downsides of using this method, which is less widely discussed. The first and perhaps biggest downside is waste. Second, its reliance on wood assemblies forming walls, floors and roofs conventionally nailed together through simple plate surfaces is structurally inefficient. It requires additional material through plates, blocking, nailers, etc., for stability that only adds to the material waste. In contrast, when we look back at the history of wood construction in airplane and boat manufacturing industries, we will see a significant transformation in the relationship of structure with skin. The history of boat construction transformed from indigenous wood practices of birch bark canoes to copper sheathing over wood to improve performance in the late 18th century and the evolution of merged assemblies that drives the industry today. In 1911, Swiss engineer Emile Ruchonnet designed the first wood monocoque structure for an airplane called the Cigare. The wing and tail assemblies consisted of thin, lightweight, and often fabric skin stretched tightly over a wood frame. This stressed skin has evolved into semi-monocoque construction, in which the skin merges with structural fins that take additional forces. It provides even greater strength with less material. The monocoque, which translates to ‘mono or single shell,’ is a structural system that supports loads and transfers them through an external enclosure system. They have largely existed outside the domain of architecture. However, this uniting of divergent systems has been demonstrated to be lighter, utilizing less material than traditional wood building practices. This paper will examine the role monocoque systems have played in the history of wood construction through lineage of boat and airplane building industries and its design potential for wood building systems in architecture through a case-study examination of a unique wood construction approach. The innovative approach uses a wood monocoque system comprised of interlocking small wood members to create thin shell assemblies for the walls, roof and floor, increasing structural efficiency and wasting less than 2% of the wood. The goal of the analysis is to expand the work of practice and the academy in order to foster deeper, more honest discourse regarding the limitations and impact of traditional wood framing.Keywords: wood building systems, material histories, monocoque systems, construction waste
Procedia PDF Downloads 781148 The Effect of Degraded Shock Absorbers on the Safety-Critical Tipping and Rolling Behaviour of Passenger Cars
Authors: Tobias Schramm, Günther Prokop
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In Germany, the number of road fatalities has been falling since 2010 at a more moderate rate than before. At the same time, the average age of all registered passenger cars in Germany is rising continuously. Studies show that there is a correlation between the age and mileage of passenger cars and the degradation of their chassis components. Various studies show that degraded shock absorbers increase the braking distance of passenger cars and have a negative impact on driving stability. The exact effect of degraded vehicle shock absorbers on road safety is still the subject of research. A shock absorber examination as part of the periodic technical inspection is only mandatory in very few countries. In Germany, there is as yet no requirement for such a shock absorber examination. More comprehensive findings on the effect of degraded shock absorbers on the safety-critical driving dynamics of passenger cars can provide further arguments for the introduction of mandatory shock absorber testing as part of the periodic technical inspection. The specific effect chains of untripped rollover accidents are also still the subject of research. However, current research results show that the high proportion of sport utility vehicles in the vehicle field significantly increases the probability of untripped rollover accidents. The aim of this work is to estimate the effect of degraded twin-tube shock absorbers on the safety-critical tipping and rolling behaviour of passenger cars, which can lead to untripped rollover accidents. A characteristic curve-based five-mass full vehicle model and a semi-physical phenomenological shock absorber model were set up, parameterized and validated. The shock absorber model is able to reproduce the damping characteristics of vehicle twin-tube shock absorbers with oil and gas loss for various excitations. The full vehicle model was validated with steering wheel angle sinus sweep driving maneuvers. The model was then used to simulate steering wheel angle sine and fishhook maneuvers, which investigate the safety-critical tipping and rolling behavior of passenger cars. The simulations were carried out in a realistic parameter space in order to demonstrate the effect of various vehicle characteristics on the effect of degraded shock absorbers. As a result, it was shown that degraded shock absorbers have a negative effect on the tipping and rolling behavior of all passenger cars. Shock absorber degradation leads to a significant increase in the observed roll angles, particularly in the range of the roll natural frequency. This superelevation has a negative effect on the wheel load distribution during the driving maneuvers investigated. In particular, the height of the vehicle's center of gravity and the stabilizer stiffness of the vehicles has a major influence on the effect of degraded shock absorbers on the overturning and rolling behaviour of passenger cars.Keywords: numerical simulation, safety-critical driving dynamics, suspension degradation, tipping and rolling behavior of passenger cars, vehicle shock absorber
Procedia PDF Downloads 121147 Effects of Culture Conditions on the Adhesion of Yeast Candida spp. and Pichia spp. to Stainless Steel with Different Polishing and Their Control
Authors: Ružica Tomičić, Zorica Tomičić, Peter Raspor
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An abundant growth of unwanted yeasts in food processing plants can lead to problems in quality and safety with significant financial losses. Candida and Pichia are the genera mainly involved in spoilage of products in the food and beverage industry. These contaminating microorganisms can form biofilms on food contact surfaces, being difficult to eradicate, increasing the probability of microbial survival and further dissemination during food processing. It is well known that biofilms are more resistant to antimicrobial agents compared to planktonic cells and this makes them difficult to eliminate. Among the strategies used to overcome resistance to antifungal drugs and preservatives, the use of natural substances such as plant extracts has shown particular promise, and many natural substances have been found to exhibit antifungal properties. This study aimed to investigated the impact of growth medium (Malt Extract broth (MEB) or Yeast Peptone Dextrose (YPD) broth) and temperatures (7°C, 37°C, 43°C for Candida strains and 7°C, 27°C, 32°C for Pichia strains) on the adhesion of Candida spp. and Pichia spp. to stainless steel (AISI 304) discs with different degrees of surface roughness (Ra = 25.20 – 961.9 nm), a material commonly used in the food industry. We also evaluated the antifungal and antiadhesion activity of plant extracts such as Humulus lupulus, Alpinia katsumadai and Evodia rutaecarpa against C. albicans, C glabrata and P. membranifaciens and investigated whether these plant extracts can interfere with biofilm formation. The adhesion was assessed by the crystal violet staining method, while the broth microdilution method CLSI M27-A3 was used to determine the minimum inhibitory concentration (MIC) of plant extracts. Our results indicated that the nutrient content of the medium significantly influenced the amount of adhered cells of the tested yeasts. The growth medium which resulted in a higher adhesion of C. albicans and C. glabrata was MEB, while for C. parapsilosis and C. krusei was YPD. In the case of P. pijperi and P. membranifaciens, YPD broth was more effective in promoting adhesion than MEB. Regarding the effect of temperature, C. albicans strain adhered to stainless steel surfaces in significantly higher level at a temperature of 43°C, while on the other hand C. glabrata, C. parapsilosis and C. krusei showed a different behavior with significantly higher adhesion at 37°C than at 7°C and 43°C. Further, the adherence ability of Pichia strains was highest at 27°C. Based on the MIC values, all plant extracts exerted significant antifungal effects with MIC values ranged from 100 to 400 μg/mL. It was observed that biofilm of C. glabrata were more resistance to plant extracts as compared to C. albicans. However, extracts of A. katsumadai and E. rutaecarpa promoted the growth and development of the preformed biofilm of P. membranifaciens. Thus, the knowledge of how these microorganisms adhere and which factors affect this phenomenon is of great importance in order to avoid their colonization on food contact surfaces.Keywords: adhesion, Candida spp., Pichia spp., plant extracts
Procedia PDF Downloads 1941146 Purification of Bacillus Lipopeptides for Diverse Applications
Authors: Vivek Rangarajan, Kim G. Clarke
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Bacillus lipopeptides are biosurfactants with wide ranging applications in the medical, food, agricultural, environmental and cosmetic industries. They are produced as a mix of three families, surfactin, iturin and fengycin, each comprising a large number of homologues of varying functionalities. Consequently, the method and degree of purification of the lipopeptide cocktail becomes particularly important if the functionality of the lipopeptide end-product is to be maximized for the specific application. However, downstream processing of Bacillus lipopeptides is particularly challenging due to the subtle variations observed in the different lipopeptide homologues and isoforms. To date, the most frequently used lipopeptide purification operations have been acid precipitation, solvent extraction, membrane ultrafiltration, adsorption and size exclusion. RP-HPLC (reverse phase high pressure liquid chromatography) also has potential for fractionation of the lipopeptide homologues. In the studies presented here, membrane ultrafiltration and RP-HPLC were evaluated for lipopeptide purification to different degrees of purities for maximum functionality. Batch membrane ultrafiltration using 50 kDa polyether sulphone (PES) membranes resulted in lipopeptide recovery of about 68% for surfactin and 82 % for fengycin. The recovery was further improved to 95% by using size-conditioned lipopeptide micelles. The conditioning of lipopeptides with Ca2+ ions resulted in uniformly sized micelles with average size of 96.4 nm and a polydispersity index of 0.18. The size conditioning also facilitated removal of impurities (molecular weight ranging between 2335-3500 Da) through operation of the system under dia-filtration mode, in a way similar to salt removal from protein by dialysis. The resultant purified lipopeptide was devoid of macromolecular impurities and could ideally suit applications in the cosmetic and food industries. Enhanced purification using RP-HPLC was carried out in an analytical C18 column, with the aim to fractionate lipopeptides into their constituent homologues. The column was eluted with mobile phase comprising acetonitrile and water over an acetonitrile gradient, 35% - 80%, over 70 minutes. The gradient elution program resulted in as many as 41 fractions of individual lipopeptide homologues. The efficacy test of these fractions against fungal phytopathogens showed that first 21 fractions, identified to be homologues of iturins and fengycins, displayed maximum antifungal activities, suitable for biocontrol in the agricultural industry. Thus, in the current study, the downstream processing of lipopeptides leading to tailor-made products for selective applications was demonstrated using two major downstream unit operations.Keywords: bacillus lipopeptides, membrane ultrafiltration, purification, RP-HPLC
Procedia PDF Downloads 2051145 Integrated Watershed Management Practice in Chelchai Hyrcanian Forests in the North of Iran
Authors: Mashad Maramaei, Behrooz Chogan, Reza Ahmadi
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Human health and the health of his watershed are inseparable. This is because a watershed is an interconnected system of "land", "water", "air" and "life". Nowadays, most of the world's watersheds show symptoms of unhealthiness and require a prompt solution. It is believed that suitable solution is a participatory and Integrated Watershed Management (IWM). In recent decades the Hyrcanian forests in the north of Iran, which belongs to the end of the third geological era, are suffering from many environmental challenges such as land degradation, increasing trends of flood, drought and accelerated soil erosion. These challenges in the main forested area of the country impose many tangible and intangible damages and human losses. This is despite the fact that in the past decades, forestry programs, watershed management and other activities in the region have been implemented in a parallel and uncoordinated manner. Therefore, recently; the Natural Resources and Watershed Management Organization has resorted to the concept of IWM planning the Hyrcanian watersheds. The Chelchai watershed as mostly degraded watershed in the eastern part of the Hyrcanian forests has been selected as a pilot watershed for implementation of the IWM. It has a drainage area of 25680 hectares and receives an average annual precipitation of 650 mm. In this mountainous region, the average temperature is 17.3 degrees Celsius. About 34% of the watershed is under cultivation, 64% under forest cover, 2% under built up areas and etc. In this research, the effectiveness or ineffectiveness of the IWM model implementation of the Natural Resources and Watershed Management Organization has been evaluated based on questionnaire method and field studies. The results indicated that IWM activities in the study area should be reconsidered and revived. Based on this research and the lessons learned during five years' experience in the Chelchai watershed; authors believe that seven important tasks are necessary for socially acceptable and successful implementation of IWM projects. These are: 1) Establishment of Local Coordination Committee (LCC) at the watershed level 2) working for development of a IWM law among government organizations to organize watershed management and eliminate parallel and contradictory activities 3) More investment on education of local communities, especially women and children 4) Development of trust builder and pattern projects that showing best agricultural and livestock management activities at each of 26 villages 5) Assigning forest protection to local communities. 6) Capacity building of government stakeholders. 7) Helping in the marketing of watershed products.Keywords: integrated watershed management, Chelchai, Hyrcanian forests, Iran
Procedia PDF Downloads 221144 Indigenous Companies in Nigeria's Oil Sector: Stages, Opportunities, and Obstacles regarding Corporate Social Responsibility
Authors: L. U. Dumuje, R. Leite
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There is an ongoing debate in terms of corporate social responsibility (CSR) initiative in Niger Delta, Nigeria, that originates from existing gap between stated objective of organizations in the Nigerian oil sector and their main activities that threaten the society. CSR in developing countries is becoming popular, and to contribute to scientific knowledge, we need to research on CSR practices and discourse in indigenous Nigeria that is scarce. Despite governments mandate in terms of unofficial blazing, methane gas is released into the air around refinery area which contributes to global warming. There is a need to understand if this practice applies to indigenous oil companies in Nigeria. To get a better understanding of CSR among indigenous oil companies in Nigeria, our study focuses on discourse and rhetoric regarding CSR. This current paper contributions is twofold: on the one hand, it aims to better understand practitioner’s rationale and fundamentals of CSR in Nigerian oil companies. On the other hand, it intends to identify the stages of CSR initiatives, advantages and difficulties of CSR implementation in indigenous Nigeria oil sector. This current paper uses the qualitative research as a methodological strategy. Instrument for data collection is semi-structured interview. Besides 28 interviews, we conduct five focus group discussions with stakeholders. Participant for this study consist of: employees, managers and executives of indigenous oil companies in Nigeria. It is relevant to mention, key informants as government institution, environmental organization and community leader/member are part of our sample. It is important that despite significant findings in some studies, there are still some gaps. To help filling this existing gaps, we have formulated some research questions, as follows: ‘What are the stages, opportunities and obstacles of having corporate social responsibility practice in indigenous oil companies in Nigeria’. This ongoing research sub-questions as follows: What are the CSR discourses and practices among indigenous companies in the Nigerian oil sector; what is the actual status regarding CSR development; what are the main perceptions of opportunities and obstacles with regard to CSR in indigenous Nigerian oil companies; who are the main stakeholders of indigenous Nigerian oil companies and their different meanings and understandings of CSR practices. Regarding the above questions, the following objectives have been determined: first, we conduct a literature review with the aim of understanding and identifying importance of CSR practises in western and developing countries. Second, this current paper identify specific characteristics of the national context in terms of CSR engagement in Nigeria, so we perform empirical research with relevant stakeholder in indigenous Nigerian, as well as key informants, in order to identify development of CSR and different perception of this praised initiative, CSR.Keywords: corporate social responsibility, indigenous, oil organizations, Nigeria, practice
Procedia PDF Downloads 1371143 Single Cell Oil of Oleaginous Fungi from Lebanese Habitats as a Potential Feed Stock for Biodiesel
Authors: M. El-haj, Z. Olama, H. Holail
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Single cell oils (SCOs) accumulated by oleaginous fungi have emerged as a potential alternative feedstock for biodiesel production. Five fungal strains were isolated from the Lebanese environment namely Fusarium oxysporum, Mucor hiemalis, Penicillium citrinum, Aspergillus tamari, and Aspergillus niger that have been selected among 39 oleaginous strains for their potential ability to accumulate lipids (lipid content was more than 40% on dry weight basis). Wide variations were recorded in the environmental factors that lead to maximum lipid production by fungi under test and were cultivated under submerged fermentation on medium containing glucose as a carbon source. The maximum lipid production was attained within 6-8 days, at pH range 6-7, 24 to 48 hours age of seed culture, 4 to 6.107 spores/ml inoculum level and 100 ml culture volume. Eleven culture conditions were examined for their significance on lipid production using Plackett-Burman factorial design. Reducing sugars and nitrogen source were the most significant factors affecting lipid production process. Maximum lipid yield was noticed with 15.62, 14.48, 12.75, 13.68 and 20.41g/l for Fusarium oxysporum, Mucor hiemalis, Penicillium citrinum, Aspergillus tamari, and Aspergillus niger respectively. A verification experiment was carried out to examine model validation and revealed more than 94% validity. The profile of extracted lipids from each fungal isolate was studied using thin layer chromatography (TLC) indicating the presence of monoacylglycerols, diaacylglycerols, free fatty acids, triacylglycerols and sterol esters. The fatty acids profiles were also determined by gas-chromatography coupled with flame ionization detector (GC-FID). Data revealed the presence of significant amount of oleic acid (29-36%), palmitic acid (18-24%), linoleic acid (26.8-35%), and low amount of other fatty acids in the extracted fungal oils which indicate that the fatty acid profiles were quite similar to that of conventional vegetable oil. The cost of lipid production could be further reduced with acid-pretreated lignocellulotic corncob waste, whey and date molasses to be utilized as the raw material for the oleaginous fungi. The results showed that the microbial lipid from the studied fungi was a potential alternative resource for biodiesel production.Keywords: agro-industrial waste products, biodiesel, fatty acid, single cell oil, Lebanese environment, oleaginous fungi
Procedia PDF Downloads 4111142 A Methodology to Virtualize Technical Engineering Laboratories: MastrLAB-VR
Authors: Ivana Scidà, Francesco Alotto, Anna Osello
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Due to the importance given today to innovation, the education sector is evolving thanks digital technologies. Virtual Reality (VR) can be a potential teaching tool offering many advantages in the field of training and education, as it allows to acquire theoretical knowledge and practical skills using an immersive experience in less time than the traditional educational process. These assumptions allow to lay the foundations for a new educational environment, involving and stimulating for students. Starting from the objective of strengthening the innovative teaching offer and the learning processes, the case study of the research concerns the digitalization of MastrLAB, High Quality Laboratory (HQL) belonging to the Department of Structural, Building and Geotechnical Engineering (DISEG) of the Polytechnic of Turin, a center specialized in experimental mechanical tests on traditional and innovative building materials and on the structures made with them. The MastrLAB-VR has been developed, a revolutionary innovative training tool designed with the aim of educating the class in total safety on the techniques of use of machinery, thus reducing the dangers arising from the performance of potentially dangerous activities. The virtual laboratory, dedicated to the students of the Building and Civil Engineering Courses of the Polytechnic of Turin, has been projected to simulate in an absolutely realistic way the experimental approach to the structural tests foreseen in their courses of study: from the tensile tests to the relaxation tests, from the steel qualification tests to the resilience tests on elements at environmental conditions or at characterizing temperatures. The research work proposes a methodology for the virtualization of technical laboratories through the application of Building Information Modelling (BIM), starting from the creation of a digital model. The process includes the creation of an independent application, which with Oculus Rift technology will allow the user to explore the environment and interact with objects through the use of joypads. The application has been tested in prototype way on volunteers, obtaining results related to the acquisition of the educational notions exposed in the experience through a virtual quiz with multiple answers, achieving an overall evaluation report. The results have shown that MastrLAB-VR is suitable for both beginners and experts and will be adopted experimentally for other laboratories of the University departments.Keywords: building information modelling, digital learning, education, virtual laboratory, virtual reality
Procedia PDF Downloads 1311141 An Exploratory Study on the Integration of Neurodiverse University Students into Mainstream Learning and Their Performance: The Case of the Jones Learning Center
Authors: George Kassar, Phillip A. Cartwright
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Based on data collected from The Jones Learning Center (JLC), University of the Ozarks, Arkansas, U.S., this study explores the impact of inclusive classroom practices on neuro-diverse college students’ and their consequent academic performance having participated in integrative therapies designed to support students who are intellectually capable of obtaining a college degree, but who require support for learning challenges owing to disabilities, AD/HD, or ASD. The purpose of this study is two-fold. The first objective is to explore the general process, special techniques, and practices of the (JLC) inclusive program. The second objective is to identify and analyze the effectiveness of the processes, techniques, and practices in supporting the academic performance of enrolled college students with learning disabilities following integration into mainstream university learning. Integrity, transparency, and confidentiality are vital in the research. All questions were shared in advance and confirmed by the concerned management at the JLC. While administering the questionnaire as well as conducted the interviews, the purpose of the study, its scope, aims, and objectives were clearly explained to all participants prior starting the questionnaire / interview. Confidentiality of all participants assured and guaranteed by using encrypted identification of individuals, thus limiting access to data to only the researcher, and storing data in a secure location. Respondents were also informed that their participation in this research is voluntary, and they may withdraw from it at any time prior to submission if they wish. Ethical consent was obtained from the participants before proceeding with videorecording of the interviews. This research uses a mixed methods approach. The research design involves collecting, analyzing, and “mixing” quantitative and qualitative methods and data to enable a research inquiry. The research process is organized based on a five-pillar approach. The first three pillars are focused on testing the first hypothesis (H1) directed toward determining the extent to the academic performance of JLC students did improve after involvement with comprehensive JLC special program. The other two pillars relate to the second hypothesis (H2), which is directed toward determining the extent to which collective and applied knowledge at JLC is distinctive from typical practices in the field. The data collected for research were obtained from three sources: 1) a set of secondary data in the form of Grade Point Average (GPA) received from the registrar, 2) a set of primary data collected throughout structured questionnaire administered to students and alumni at JLC, and 3) another set of primary data collected throughout interviews conducted with staff and educators at JLC. The significance of this study is two folds. First, it validates the effectiveness of the special program at JLC for college-level students who learn differently. Second, it identifies the distinctiveness of the mix of techniques, methods, and practices, including the special individualized and personalized one-on-one approach at JLC.Keywords: education, neuro-diverse students, program effectiveness, Jones learning center
Procedia PDF Downloads 741140 The Impact of the Covid-19 Crisis on the Information Behavior in the B2B Buying Process
Authors: Stehr Melanie
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The availability of apposite information is essential for the decision-making process of organizational buyers. Due to the constraints of the Covid-19 crisis, information channels that emphasize face-to-face contact (e.g. sales visits, trade shows) have been unavailable, and usage of digitally-driven information channels (e.g. videoconferencing, platforms) has skyrocketed. This paper explores the question in which areas the pandemic induced shift in the use of information channels could be sustainable and in which areas it is a temporary phenomenon. While information and buying behavior in B2C purchases has been regularly studied in the last decade, the last fundamental model of organizational buying behavior in B2B was introduced by Johnston and Lewin (1996) in times before the advent of the internet. Subsequently, research efforts in B2B marketing shifted from organizational buyers and their decision and information behavior to the business relationships between sellers and buyers. This study builds on the extensive literature on situational factors influencing organizational buying and information behavior and uses the economics of information theory as a theoretical framework. The research focuses on the German woodworking industry, which before the Covid-19 crisis was characterized by a rather low level of digitization of information channels. By focusing on an industry with traditional communication structures, a shift in information behavior induced by an exogenous shock is considered a ripe research setting. The study is exploratory in nature. The primary data source is 40 in-depth interviews based on the repertory-grid method. Thus, 120 typical buying situations in the woodworking industry and the information and channels relevant to them are identified. The results are combined into clusters, each of which shows similar information behavior in the procurement process. In the next step, the clusters are analyzed in terms of the post and pre-Covid-19 crisis’ behavior identifying stable and dynamic information behavior aspects. Initial results show that, for example, clusters representing search goods with low risk and complexity suggest a sustainable rise in the use of digitally-driven information channels. However, in clusters containing trust goods with high significance and novelty, an increased return to face-to-face information channels can be expected after the Covid-19 crisis. The results are interesting from both a scientific and a practical point of view. This study is one of the first to apply the economics of information theory to organizational buyers and their decision and information behavior in the digital information age. Especially the focus on the dynamic aspects of information behavior after an exogenous shock might contribute new impulses to theoretical debates related to the economics of information theory. For practitioners - especially suppliers’ marketing managers and intermediaries such as publishers or trade show organizers from the woodworking industry - the study shows wide-ranging starting points for a future-oriented segmentation of their marketing program by highlighting the dynamic and stable preferences of elaborated clusters in the choice of their information channels.Keywords: B2B buying process, crisis, economics of information theory, information channel
Procedia PDF Downloads 1841139 Development of a Stable RNAi-Based Biological Control for Sheep Blowfly Using Bentonite Polymer Technology
Authors: Yunjia Yang, Peng Li, Gordon Xu, Timothy Mahony, Bing Zhang, Neena Mitter, Karishma Mody
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Sheep flystrike is one of the most economically important diseases affecting the Australian sheep and wool industry (>356M/annually). Currently, control of Lucillia cuprina relies almost exclusively on chemicals controls and the parasite has developed resistance to nearly all control chemicals used in the past. It is therefore critical to develop an alternative solution for the sustainable control and management of flystrike. RNA interference (RNAi) technologies have been successfully explored in multiple animal industries for developing parasites controls. This research project aims to develop a RNAi based biological control for sheep blowfly. Double-stranded RNA (dsRNA) has already proven successful against viruses, fungi and insects. However, the environmental instability of dsRNA is a major bottleneck for successful RNAi. Bentonite polymer (BenPol) technology can overcome this problem, as it can be tuned for the controlled release of dsRNA in the gut challenging pH environment of the blowfly larvae, prolonging its exposure time to and uptake by target cells. To investigate the potential of BenPol technology for dsRNA delivery, four different BenPol carriers were tested for their dsRNA loading capabilities, and three of them were found to be capable of affording dsRNA stability under multiple temperatures (4°C, 22°C, 40°C, 55°C) in sheep serum. Based on stability results, dsRNA from potential targeted genes was loaded onto BenPol carriers and tested in larvae feeding assays, three genes resulting in knockdowns. Meanwhile, a primary blowfly embryo cell line (BFEC) derived from L. cuprina embryos was successfully established, aim for an effective insect cell model for testing RNAi efficacy for preliminary assessments and screening. The results of this study establish that the dsRNA is stable when loaded on BenPol particles, unlike naked dsRNA rapidly degraded in sheep serum. The stable nanoparticle delivery system offered by BenPol technology can protect and increase the inherent stability of dsRNA molecules at higher temperatures in a complex biological fluid like serum, providing promise for its future use in enhancing animal protection.Keywords: flystrike, RNA interference, bentonite polymer technology, Lucillia cuprina
Procedia PDF Downloads 921138 An Improved Approach for Hybrid Rocket Injection System Design
Authors: M. Invigorito, G. Elia, M. Panelli
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Hybrid propulsion combines beneficial properties of both solid and liquid rockets, such as multiple restarts, throttability as well as simplicity and reduced costs. A nitrous oxide (N2O)/paraffin-based hybrid rocket engine demonstrator is currently under development at the Italian Aerospace Research Center (CIRA) within the national research program HYPROB, funded by the Italian Ministry of Research. Nitrous oxide belongs to the class of self-pressurizing propellants that exhibit a high vapor pressure at standard ambient temperature. This peculiar feature makes those fluids very attractive for space rocket applications because it avoids the use of complex pressurization systems, leading to great benefits in terms of weight savings and reliability. To avoid feed-system-coupled instabilities, the phase change is required to occur through the injectors. In this regard, the oxidizer is stored in liquid condition while target chamber pressures are designed to lie below vapor pressure. The consequent cavitation and flash vaporization constitute a remarkably complex phenomenology that arises great modelling challenges. Thus, it is clear that the design of the injection system is fundamental for the full exploitation of hybrid rocket engine throttability. The Analytical Hierarchy Process has been used to select the injection architecture as best compromise among different design criteria such as functionality, technology innovation and cost. The impossibility to use engineering simplified relations for the dimensioning of the injectors led to the needs of applying a numerical approach based on OpenFOAM®. The numerical tool has been validated with selected experimental data from literature. Quantitative, as well as qualitative comparisons are performed in terms of mass flow rate and pressure drop across the injector for several operating conditions. The results show satisfactory agreement with the experimental data. Modeling assumptions, together with their impact on numerical predictions are discussed in the paper. Once assessed the reliability of the numerical tool, the injection plate has been designed and sized to guarantee the required amount of oxidizer in the combustion chamber and therefore to assure high combustion efficiency. To this purpose, the plate has been designed with multiple injectors whose number and diameter have been selected in order to reach the requested mass flow rate for the two operating conditions of maximum and minimum thrust. The overall design has been finally verified through three-dimensional computations in cavitating non-reacting conditions and it has been verified that the proposed design solution is able to guarantee the requested values of mass flow rates.Keywords: hybrid rocket, injection system design, OpenFOAM®, cavitation
Procedia PDF Downloads 2161137 Women's Perceptions of Zika Virus Prevention Recommendations: A Tale of Two Cities within Fortaleza, Brazil
Authors: Jeni Stolow, Lina Moses, Carl Kendall
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Zika virus (ZIKV) reemerged as a global threat in 2015 with Brazil at its epicenter. Brazilians have a long history of combatting Aedes aegypti mosquitos as it is a common vector for dengue, chikungunya, and yellow fever. As a response to the epidemic, public health authorities promoted ZIKV prevention behaviors such as mosquito bite prevention, reproductive counseling for women who are pregnant or contemplating pregnancy, pregnancy avoidance, and condom use. Most prevention efforts from Brazil focused on the mosquito vector- utilizing recycled dengue approaches without acknowledging the context in which women were able to adhere to these prevention messages. This study used qualitative methods to explore how women in Fortaleza, Brazil perceive ZIKV, the Brazilian authorities’ ZIKV prevention recommendations, and the feasibility of adhering to these recommendations. A core study aim was to look at how women perceive their physical, social, and natural environment as it impacts women’s ability to adhere to ZIKV prevention behaviors. A Rapid Anthropological Assessment (RAA) containing observations, informational interviews, and semi-structured in-depth interviews were utilized for data collection. The study utilized Grounded Theory as the systematic inductive method of analyzing the data collected. Interviews were conducted with 35 women of reproductive age (15-39 years old), who primarily utilize the public health system. It was found that women’s self-identified economic class was associated with how strongly women felt they could prevent ZIKV. All women interviewed technically belong to the C-class, the middle economic class. Although all members of the same economic class, there was a divide amongst participants as to who perceived themselves as higher C-class versus lower C-class. How women saw their economic status was dictated by how they perceived their physical, social, and natural environment. Women further associated their environment and their economic class to their likelihood of contracting ZIKV, their options for preventing ZIKV, their ability to prevent ZIKV, and their willingness to attempt to prevent ZIKV. Women’s perceived economic status was found to relate to their structural environment (housing quality, sewage, and locations to supplies), social environment (family and peer norms), and natural environment (wetland areas, natural mosquito breeding sites, and cyclical nature of vectors). Findings from this study suggest that women’s perceived environment and economic status impact their perceived feasibility and desire to attempt behaviors to prevent ZIKV. Although ZIKV has depleted from epidemic to endemic status, it is suggested that the virus will return as cyclical outbreaks like that seen with similar arboviruses such as dengue and chikungunya. As the next ZIKV epidemic approaches it is essential to understand how women perceive themselves, their abilities, and their environments to best aid the prevention of ZIKV.Keywords: Aedes aegypti, environment, prevention, qualitative, zika
Procedia PDF Downloads 1331136 Transition from Linear to Circular Business Models with Service Design Methodology
Authors: Minna-Maari Harmaala, Hanna Harilainen
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Estimates of the economic value of transitioning to circular economy models vary but it has been estimated to represent $1 trillion worth of new business into the global economy. In Europe alone, estimates claim that adopting circular-economy principles could not only have environmental and social benefits but also generate a net economic benefit of €1.8 trillion by 2030. Proponents of a circular economy argue that it offers a major opportunity to increase resource productivity, decrease resource dependence and waste, and increase employment and growth. A circular system could improve competitiveness and unleash innovation. Yet, most companies are not capturing these opportunities and thus the even abundant circular opportunities remain uncaptured even though they would seem inherently profitable. Service design in broad terms relates to developing an existing or a new service or service concept with emphasis and focus on the customer experience from the onset of the development process. Service design may even mean starting from scratch and co-creating the service concept entirely with the help of customer involvement. Service design methodologies provide a structured way of incorporating customer understanding and involvement in the process of designing better services with better resonance to customer needs. A business model is a depiction of how the company creates, delivers, and captures value; i.e. how it organizes its business. The process of business model development and adjustment or modification is also called business model innovation. Innovating business models has become a part of business strategy. Our hypothesis is that in addition to linear models still being easier to adopt and often with lower threshold costs, companies lack an understanding of how circular models can be adopted into their business and how customers will be willing and ready to adopt the new circular business models. In our research, we use robust service design methodology to develop circular economy solutions with two case study companies. The aim of the process is to not only develop the service concepts and portfolio, but to demonstrate the willingness to adopt circular solutions exists in the customer base. In addition to service design, we employ business model innovation methods to develop, test, and validate the new circular business models further. The results clearly indicate that amongst the customer groups there are specific customer personas that are willing to adopt and in fact are expecting the companies to take a leading role in the transition towards a circular economy. At the same time, there is a group of indifferents, to whom the idea of circularity provides no added value. In addition, the case studies clearly show what changes adoption of circular economy principles brings to the existing business model and how they can be integrated.Keywords: business model innovation, circular economy, circular economy business models, service design
Procedia PDF Downloads 1351135 Changing Employment Relations Practices in Hong Kong: Cases of Two Multinational Retail Banks since 1997
Authors: Teresa Shuk-Ching Poon
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This paper sets out to examine the changing employment relations practices in Hong Kong’s retail banking sector over a period of more than 10 years. The major objective of the research is to examine whether and to what extent local institutional influences have overshadowed global market forces in shaping strategic management decisions and employment relations practices in Hong Kong, with a view to drawing implications to comparative employment relations studies. Examining the changing pattern of employment relations, this paper finds the industrial relations strategic choice model (Kochan, McKersie and Cappelli, 1984) appropriate to use as a framework for the study. Four broad aspects of employment relations are examined, including work organisation and job design; staffing and labour adjustment; performance appraisal, compensation and employee development; and labour unions and employment relations. Changes in the employment relations practices in two multinational retail banks operated in Hong Kong are examined in detail. The retail banking sector in Hong Kong is chosen as a case to examine as it is a highly competitive segment in the financial service industry very much susceptible to global market influences. This is well illustrated by the fact that Hong Kong was hit hard by both the Asian and the Global Financial Crises. This sector is also subject to increasing institutional influences, especially after the return of Hong Kong’s sovereignty to the People’s Republic of China (PRC) since 1997. The case study method is used as it is a suitable research design able to capture the complex institutional and environmental context which is the subject-matter to be examined in the paper. The paper concludes that operation of the retail banks in Hong Kong has been subject to both institutional and global market changes at different points in time. Information obtained from the two cases examined tends to support the conclusion that the relative significance of institutional as against global market factors in influencing retail banks’ operation and their employment relations practices is depended very much on the time in which these influences emerged and the scale and intensity of these influences. This case study highlights the importance of placing comparative employment relations studies within a context where employment relations practices in different countries or different regions/cities within the same country could be examined and compared over a longer period of time to make the comparison more meaningful.Keywords: employment relations, institutional influences, global market forces, strategic management decisions, retail banks, Hong Kong
Procedia PDF Downloads 4021134 Effects of Lime and N100 on the Growth and Phytoextraction Capability of a Willow Variety (S. Viminalis × S. Schwerinii × S. Dasyclados) Grown in Contaminated Soils
Authors: Mir Md. Abdus Salam, Muhammad Mohsin, Pertti Pulkkinen, Paavo Pelkonen, Ari Pappinen
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Soil and water pollution caused by extensive mining practices can adversely affect environmental components, such as humans, animals, and plants. Despite a generally positive contribution to society, mining practices have become a serious threat to biological systems. As metals do not degrade completely, they require immobilization, toxicity reduction, or removal. A greenhouse experiment was conducted to evaluate the effects of lime and N100 (11-amino-1-hydroxyundecylidene) chelate amendment on the growth and phytoextraction potential of the willow variety Klara (S. viminalis × S. schwerinii × S. dasyclados) grown in soils heavily contaminated with copper (Cu). The plants were irrigated with tap or processed water (mine wastewater). The sequential extraction technique and inductively coupled plasma-mass spectrometry (ICP-MS) tool were used to determine the extractable metals and evaluate the fraction of metals in the soil that could be potentially available for plant uptake. The results suggest that the combined effects of the contaminated soil and processed water inhibited growth parameter values. In contrast, the accumulation of Cu in the plant tissues was increased compared to the control. When the soil was supplemented with lime and N100; growth parameter and resistance capacity were significantly higher compared to unamended soil treatments, especially in the contaminated soil treatments. The combined lime- and N100-amended soil treatment produced higher growth rate of biomass, resistance capacity and phytoextraction efficiency levels relative to either the lime-amended or the N100-amended soil treatments. This study provides practical evidence of the efficient chelate-assisted phytoextraction capability of Klara and highlights its potential as a viable and inexpensive novel approach for in-situ remediation of Cu-contaminated soils and mine wastewaters. Abandoned agricultural, industrial and mining sites can also be utilized by a Salix afforestation program without conflict with the production of food crops. This kind of program may create opportunities for bioenergy production and economic development, but contamination levels should be examined before bioenergy products are used.Keywords: copper, Klara, lime, N100, phytoextraction
Procedia PDF Downloads 1461133 Concussion: Clinical and Vocational Outcomes from Sport Related Mild Traumatic Brain Injury
Authors: Jack Nash, Chris Simpson, Holly Hurn, Ronel Terblanche, Alan Mistlin
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There is an increasing incidence of mild traumatic brain injury (mTBI) cases throughout sport and with this, a growing interest from governing bodies to ensure these are managed appropriately and player welfare is prioritised. The Berlin consensus statement on concussion in sport recommends a multidisciplinary approach when managing those patients who do not have full resolution of mTBI symptoms. There are as of yet no standardised guideline to follow in the treatment of complex cases mTBI in athletes. The aim of this project was to analyse the outcomes, both clinical and vocational, of all patients admitted to the mild Traumatic Brain Injury (mTBI) service at the UK’s Defence Military Rehabilitation Centre Headley Court between 1st June 2008 and 1st February 2017, as a result of a sport induced injury, and evaluate potential predictive indicators of outcome. Patients were identified from a database maintained by the mTBI service. Clinical and occupational outcomes were ascertained from medical and occupational employment records, recorded prospectively, at time of discharge from the mTBI service. Outcomes were graded based on the vocational independence scale (VIS) and clinical documentation at discharge. Predictive indicators including referral time, age at time of injury, previous mental health diagnosis and a financial claim in place at time of entry to service were assessed using logistic regression. 45 Patients were treated for sport-related mTBI during this time frame. Clinically 96% of patients had full resolution of their mTBI symptoms after input from the mTBI service. 51% of patients returned to work at their previous vocational level, 4% had ongoing mTBI symptoms, 22% had ongoing physical rehabilitation needs, 11% required mental health input and 11% required further vestibular rehabilitation. Neither age, time to referral, pre-existing mental health condition nor compensation seeking had a significant impact on either vocational or clinical outcome in this population. The vast majority of patients reviewed in the mTBI clinic had persistent symptoms which could not be managed in primary care. A consultant-led, multidisciplinary approach to the diagnosis and management of mTBI has resulted in excellent clinical outcomes in these complex cases. High levels of symptom resolution suggest that this referral and treatment pathway is successful and is a model which could be replicated in other organisations with consultant led input. Further understanding of both predictive and individual factors would allow clinicians to focus treatments on those who are most likely to develop long-term complications following mTBI. A consultant-led, multidisciplinary service ensures a large number of patients will have complete resolution of mTBI symptoms after sport-related mTBI. Further research is now required to ascertain the key predictive indicators of outcome following sport-related mTBI.Keywords: brain injury, concussion, neurology, rehabilitation, sports injury
Procedia PDF Downloads 1571132 The Life Skills Project: Client-Centered Approaches to Life Skills Acquisition for Homeless and At-Risk Populations
Authors: Leah Burton, Sara Cumming, Julianne DiSanto
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Homelessness is a widespread and complex problem in Canada and around the globe. Many Canadians will face homelessness at least once in their lifetime, with several experiencing subsequent bouts or cyclical patterns of housing precarity. While a Housing First approach to homelessness is a long-standing and widely accepted best practice, it is also recognized that the acquisition of life skills is an effective way to reduce cycles of homelessness. Indeed, when individuals are provided with a range of life skills—such as (but not limited to) financial literacy, household management, interpersonal skills, critical thinking, and resource management—they are given the tools required to maintain long-term Housing for a lifetime; thus reducing a repetitive need for services. However, there is limited research regarding the best ways to teach life skills, a problem that has been further complicated in a post-pandemic world, where services are being delivered online or in a hybrid model of care. More than this, it is difficult to provide life skills on a large scale without losing a client-centered approach to services. This lack of client-centeredness is also seen in the lack of attention to culturally sensitive life skills, which consider the diverse needs of individuals and imbed equity, diversity, and inclusion (EDI) within the skills being taught. This study aims to fill these identified gaps in the literature by employing a community-engaged (CER) approach. Academic, government, funders, front-line staff, and clients at 15 not-for-profits from across the Greater Toronto Area in Ontario, Canada, collaborated to co-create a virtual, client-centric, EDI-informed life skill learning management system. A triangulation methodology was utilized for this research. An environmental scan was conducted for current best practices, and over 100 front-line staff (including workers, managers, and executive directors who work with homeless populations) participated in two separate Creative Problem Solving Sessions. Over 200 individuals with experience in homelessness completed quantitative and open-ended surveys. All sections of this research aimed to discover the areas of skills that individuals need to maintain Housing and to ascertain what a more client-driven EDI approach to life skills training should include. This presentation will showcase the findings on which life skills are deemed essential for homeless and precariously housed individuals.Keywords: homelessness, housing first, life skills, community engaged research, client- centered
Procedia PDF Downloads 1011131 Internal Concept of Integrated Health by Agrarian Society in Malagasy Highlands for the Last Century
Authors: O. R. Razanakoto, L. Temple
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Living in a least developed country, the Malagasy society has a weak capacity to internalize progress, including health concerns. Since the arrival in the fifteenth century of Arabic script, called Sorabe, that was mainly dedicated to the aristocracy, until the colonial era beginning at the end of the nineteenth century and that has popularized the current usual script of the occidental civilization, the upcoming manuscripts that deal with apparent scientific or at least academic issue have been slowly established. So that, the Malagasy communities’ way of life is not well documented yet to allow a precise understanding of the major concerns, reason, and purpose of the existence of the farmers that compose them. A question arises, according to literature, how does Malagasy community that is dominated by agrarian society conceive the conservation of its wellbeing? This study aims to emphasize the scope and the limits of the « One Health » concept or of the Health Integrated Approach (HIA) that evolves at global scale, with regard to the specific context of local Malagasy smallholder farms. It is expected to identify how this society represents linked risks and the mechanisms between human health, animal health, plant health, and ecosystem health within the last 100 years. To do so, the framework to conduct systematic review for agricultural research has been deployed to access available literature. This task has been coupled with the reading of articles that are not indexed by online scientific search engine but that mention part of a history of agriculture and of farmers in Madagascar. This literature review has informed the interactions between human illnesses and those affecting animals and plants (breeded or wild) with any unexpected event (ecological or economic) that has modified the equilibrium of the ecosystem, or that has disturbed the livelihoods of agrarian communities. Besides, drivers that may either accentuate or attenuate the devasting effects of these illnesses and changes were revealed. The study has established that the reasons of human worries are not only physiological. Among the factors that regulate global health, food system and contemporary medicine have helped to the improvement of life expectancy from 55 to 63 years in Madagascar during the last 50 years. However, threats to global health are still occurring. New human or animal illnesses and livestock / plant pathology or enemies may also appear, whereas ancient illnesses that are supposed to have disappeared may be back. This study has highlighted how much important are the risks associated to the impact of unmanaged externalities that weaken community’s life. Many risks, and also solutions, come from abroad and have long term effects even though those happen as punctual event. Thus, a constructivist strategy is suggested to the « One Health » global concept throughout the record of local facts. This approach should facilitate the exploration of methodological pathways and the identification of relevant indicators for research related to HIA.Keywords: agrarian system, health integrated approach, history, madagascar, resilience, risk
Procedia PDF Downloads 1101130 The Effects of Resident Fathers on the Children in South Africa: The Case of Selected Household in Golf View, Alice Town, Eastern Cape Province
Authors: Gabriel Acha Ekobi
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Fathers play a crucial role in meeting family needs such as affection, protection, and socio-economic needs of children in the world in general and South Africa in particular. Fathers’ role in children’s lives is important in providing socialization, leadership skills, and teaching societal norms. Fathers influence is very significant for children’s well-being and development as it provides the child with moral lessons, guidance, and economic support. However, there is a paucity of information regarding the effects of fathers on children. In addition, despite legal frameworks such as the African Charter on the Rights and Welfare of the child (1999) introduced by the African Union to promote child rights nevertheless, it appears maltreatment, abuse, and poor health care continue to face children. Also, the Constitution of 1996 of the Republic of South Africa (Section 28 of the Bill of Rights) and the Children’s Act 38 of 2005 were introduced by the South African government to foster the rights of children. Nevertheless, these legal frameworks remain ineffective as children’s rights are still neglected by resident fathers. This paper explores the impact of resident fathers on children in the Golf View, Alice town of the Eastern Cape Province, South Africa. A qualitative research method and an exploratory research design were utilized, and 30 participants took part in the study. The participants comprised of single mothers or caregivers of children, resident fathers and social workers. Eighteen (18) single mothers or caregivers, 10 resident fathers, and two (2) social workers participated in the study. Data was collected using semi-structured and unstructured interviews and analysed thematically. Two main themes were identified: the role of fathers on children and the effects of resident fathers on children. The study found that the presence of fathers in the lives of children prevented psychosocial issues such as stress, depression, violence, and substance abuse. A father’s presence in a household was crucial in instilling moral values in children. This allowed them to build positive characters such as respect, kindness, humility, and compassion. Children with more involved fathers tend to have fewer impulse control problems, longer attention spans, and a higher level of sociability. The study concludes that the fathers’ role prevented anxiety, depression, and stress and led to the improvement of children’s education performance. Nevertheless, the absence of a father as a role model to act as a leader by instilling moral values hinders positive behaviours in children. This study recommended that occupational training and life skills programmes should be introduced by the government and other stakeholders to empower the fathers as this might provide the platform for them to bring up their children properly.Keywords: children, fathering, household, resident, single parent
Procedia PDF Downloads 521129 Monitoring of Rice Phenology and Agricultural Practices from Sentinel 2 Images
Authors: D. Courault, L. Hossard, V. Demarez, E. Ndikumana, D. Ho Tong Minh, N. Baghdadi, F. Ruget
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In the global change context, efficient management of the available resources has become one of the most important topics, particularly for sustainable crop development. Timely assessment with high precision is crucial for water resource and pest management. Rice cultivated in Southern France in the Camargue region must face a challenge, reduction of the soil salinity by flooding and at the same time reduce the number of herbicides impacting negatively the environment. This context has lead farmers to diversify crop rotation and their agricultural practices. The objective of this study was to evaluate this crop diversity both in crop systems and in agricultural practices applied to rice paddy in order to quantify the impact on the environment and on the crop production. The proposed method is based on the combined use of crop models and multispectral data acquired from the recent Sentinel 2 satellite sensors launched by the European Space Agency (ESA) within the homework of the Copernicus program. More than 40 images at fine spatial resolution (10m in the optical range) were processed for 2016 and 2017 (with a revisit time of 5 days) to map crop types using random forest method and to estimate biophysical variables (LAI) retrieved by inversion of the PROSAIL canopy radiative transfer model. Thanks to the high revisit time of Sentinel 2 data, it was possible to monitor the soil labor before flooding and the second sowing made by some farmers to better control weeds. The temporal trajectories of remote sensing data were analyzed for various rice cultivars for defining the main parameters describing the phenological stages useful to calibrate two crop models (STICS and SAFY). Results were compared to surveys conducted with 10 farms. A large variability of LAI has been observed at farm scale (up to 2-3m²/m²) which induced a significant variability in the yields simulated (up to 2 ton/ha). Observations on more than 300 fields have also been collected on land use. Various maps were elaborated, land use, LAI, flooding and sowing, and harvest dates. All these maps allow proposing a new typology to classify these paddy crop systems. Key phenological dates can be estimated from inverse procedures and were validated against ground surveys. The proposed approach allowed to compare the years and to detect anomalies. The methods proposed here can be applied at different crops in various contexts and confirm the potential of remote sensing acquired at fine resolution such as the Sentinel2 system for agriculture applications and environment monitoring. This study was supported by the French national center of spatial studies (CNES, funded by the TOSCA).Keywords: agricultural practices, remote sensing, rice, yield
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