Search results for: socio-scientific issues-based learning method
Commenced in January 2007
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Edition: International
Paper Count: 23981

Search results for: socio-scientific issues-based learning method

1331 Leadership in the Emergence Paradigm: a Literature Review on the Medusa Principles

Authors: Everard van Kemenade

Abstract:

Many quality improvement activities are planned. Leaders are strongly involved in missions, visions and strategic planning. They use, consciously or unconsciously, the PDCA-cycle, also know as the Deming cycle. After the planning, the plans are carried out and the results or effects are measured. If the results show that the goals in the plan have not been achieved, adjustments are made in the next plan or in the execution of the processes. Then, the cycle is run through again. Traditionally, the PDCA-cycle is advocated as a means to an end. However, PDCA is especially fit for planned, ordered, certain contexts. It fits with the empirical and referential quality paradigm. For uncertain, unordered, unplanned processes, something else might be needed instead of Plan-Do-Check-Act. Due to the complexity of our society, the influence of the context, and the uncertainty in our world nowadays, not every activity can be planned anymore. At the same time organisations need to be more innovative than ever. That provides leaders with ‘wicked tendencies’. However, that raises the question how one can innovate without being able to plan? Complexity science studies the interactions of a diverse group of agents that bring about change in times of uncertainty, e.g. when radical innovation is co-created. This process is called emergence. This research study explores the role of leadership in the emergence paradigm. Aim of the article is to study the way that leadership can support the emergence of innovation in a complex context. First, clarity is given on the concepts used in the research question: complexity, emergence, innovation and leadership. Thereafter a literature search is conducted to answer the research question. The topics ‘emergent leadership’ or ‘complexity leadership’ are chosen for an exploratory search in Google and Google Scholar using the berry picking method. Exclusion criterion is emergence in other disciplines than organizational development or in the meaning of ‘arising’. The literature search conducted gave 45 hits. Twenty-seven articles were excluded after reading the title and abstract because they did not research the topic of emergent leadership and complexity. After reading the remaining articles as a whole one more was excluded because the article used emergent in the limited meaning of ‗arising‘ and eight more were excluded because the topic did not match the research question of this article. That brings the total of the search to 17 articles. The useful conclusions from the articles are merged and grouped together under overarching topics, using thematic analysis. The findings are that 5 topics prevail when looking at possibilities for leadership to facilitate innovation: enabling, sharing values, dreaming, interacting, context sensitivity and adaptivity. Together they form In Dutch the acronym Medusa.

Keywords: complexity science, emergence, leadership in the emergence paradigm, innovation, the Medusa principles

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1330 Increment of Panel Flutter Margin Using Adaptive Stiffeners

Authors: S. Raja, K. M. Parammasivam, V. Aghilesh

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Fluid-structure interaction is a crucial consideration in the design of many engineering systems such as flight vehicles and bridges. Aircraft lifting surfaces and turbine blades can fail due to oscillations caused by fluid-structure interaction. Hence, it is focussed to study the fluid-structure interaction in the present research. First, the effect of free vibration over the panel is studied. It is well known that the deformation of a panel and flow induced forces affects one another. The selected panel has a span 300mm, chord 300mm and thickness 2 mm. The project is to study, the effect of cross-sectional area and the stiffener location is carried out for the same panel. The stiffener spacing is varied along both the chordwise and span-wise direction. Then for that optimal location the ideal stiffener length is identified. The effect of stiffener cross-section shapes (T, I, Hat, Z) over flutter velocity has been conducted. The flutter velocities of the selected panel with two rectangular stiffeners of cantilever configuration are estimated using MSC NASTRAN software package. As the flow passes over the panel, deformation takes place which further changes the flow structure over it. With increasing velocity, the deformation goes on increasing, but the stiffness of the system tries to dampen the excitation and maintain equilibrium. But beyond a critical velocity, the system damping suddenly becomes ineffective, so it loses its equilibrium. This estimated in NASTRAN using PK method. The first 10 modal frequencies of a simple panel and stiffened panel are estimated numerically and are validated with open literature. A grid independence study is also carried out and the modal frequency values remain the same for element lengths less than 20 mm. The current investigation concludes that the span-wise stiffener placement is more effective than the chord-wise placement. The maximum flutter velocity achieved for chord-wise placement is 204 m/s while for a span-wise arrangement it is augmented to 963 m/s for the stiffeners location of ¼ and ¾ of the chord from the panel edge (50% of chord from either side of the mid-chord line). The flutter velocity is directly proportional to the stiffener cross-sectional area. A significant increment in flutter velocity from 218m/s to 1024m/s is observed for the stiffener lengths varying from 50% to 60% of the span. The maximum flutter velocity above Mach 3 is achieved. It is also observed that for a stiffened panel, the full effect of stiffener can be achieved only when the stiffener end is clamped. Stiffeners with Z cross section incremented the flutter velocity from 142m/s (Panel with no stiffener) to 328 m/s, which is 2.3 times that of simple panel.

Keywords: stiffener placement, stiffener cross-sectional area, stiffener length, stiffener cross sectional area shape

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1329 Determination of Activation Energy for Thermal Decomposition of Selected Soft Tissues Components

Authors: M. Ekiert, T. Uhl, A. Mlyniec

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Tendons are the biological soft tissue structures composed of collagen, proteoglycan, glycoproteins, water and cells of extracellular matrix (ECM). Tendons, which primary function is to transfer force generated by the muscles to the bones causing joints movement, are exposed to many micro and macro damages. In fact, tendons and ligaments trauma are one of the most numerous injuries of human musculoskeletal system, causing for many people (particularly for athletes and physically active people), recurring disorders, chronic pain or even inability of movement. The number of tendons reconstruction and transplantation procedures is increasing every year. Therefore, studies on soft tissues storage conditions (influencing i.e. tissue aging) seem to be an extremely important issue. In this study, an atomic-scale investigation on the kinetics of decomposition of two selected tendon components – collagen type I (which forms a 60-85% of a tendon dry mass) and elastin protein (which combine with ECM creates elastic fibers of connective tissues) is presented. A molecular model of collagen and elastin was developed based on crystal structure of triple-helical collagen-like 1QSU peptide and P15502 human elastin protein, respectively. Each model employed 4 linear strands collagen/elastin strands per unit cell, distributed in 2x2 matrix arrangement, placed in simulation box filled with water molecules. A decomposition phenomena was simulated with molecular dynamics (MD) method using ReaxFF force field and periodic boundary conditions. A set of NVT-MD runs was performed for 1000K temperature range in order to obtained temperature-depended rate of production of decomposition by-products. Based on calculated reaction rates activation energies and pre-exponential factors, required to formulate Arrhenius equations describing kinetics of decomposition of tested soft tissue components, were calculated. Moreover, by adjusting a model developed for collagen, system scalability and correct implementation of the periodic boundary conditions were evaluated. An obtained results provide a deeper insight into decomposition of selected tendon components. A developed methodology may also be easily transferred to other connective tissue elements and therefore might be used for further studies on soft tissues aging.

Keywords: decomposition, molecular dynamics, soft tissue, tendons

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1328 Calibration of 2D and 3D Optical Measuring Instruments in Industrial Environments at Submillimeter Range

Authors: Alberto Mínguez-Martínez, Jesús de Vicente y Oliva

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Modern manufacturing processes have led to the miniaturization of systems and, as a result, parts at the micro-and nanoscale are produced. This trend seems to become increasingly important in the near future. Besides, as a requirement of Industry 4.0, the digitalization of the models of production and processes makes it very important to ensure that the dimensions of newly manufactured parts meet the specifications of the models. Therefore, it is possible to reduce the scrap and the cost of non-conformities, ensuring the stability of the production at the same time. To ensure the quality of manufactured parts, it becomes necessary to carry out traceable measurements at scales lower than one millimeter. Providing adequate traceability to the SI unit of length (the meter) to 2D and 3D measurements at this scale is a problem that does not have a unique solution in industrial environments. Researchers in the field of dimensional metrology all around the world are working on this issue. A solution for industrial environments, even if it is not complete, will enable working with some traceability. At this point, we believe that the study of the surfaces could provide us with a first approximation to a solution. Among the different options proposed in the literature, the areal topography methods may be the most relevant because they could be compared to those measurements performed using Coordinate Measuring Machines (CMM’s). These measuring methods give (x, y, z) coordinates for each point, expressing it in two different ways, either expressing the z coordinate as a function of x, denoting it as z(x), for each Y-axis coordinate, or as a function of the x and y coordinates, denoting it as z (x, y). Between others, optical measuring instruments, mainly microscopes, are extensively used to carry out measurements at scales lower than one millimeter because it is a non-destructive measuring method. In this paper, the authors propose a calibration procedure for the scales of optical measuring instruments, particularizing for a confocal microscope, using material standards easy to find and calibrate in metrology and quality laboratories in industrial environments. Confocal microscopes are measuring instruments capable of filtering the out-of-focus reflected light so that when it reaches the detector, it is possible to take pictures of the part of the surface that is focused. Varying and taking pictures at different Z levels of the focus, a specialized software interpolates between the different planes, and it could reconstruct the surface geometry into a 3D model. As it is easy to deduce, it is necessary to give traceability to each axis. As a complementary result, the roughness Ra parameter will be traced to the reference. Although the solution is designed for a confocal microscope, it may be used for the calibration of other optical measuring instruments by applying minor changes.

Keywords: industrial environment, confocal microscope, optical measuring instrument, traceability

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1327 Dry Modifications of PCL/Chitosan/PCL Tissue Scaffolds

Authors: Ozan Ozkan, Hilal Turkoglu Sasmazel

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Natural polymers are widely used in tissue engineering applications, because of their biocompatibility, biodegradability and solubility in the physiological medium. On the other hand, synthetic polymers are also widely utilized in tissue engineering applications, because they carry no risk of infectious diseases and do not cause immune system reaction. However, the disadvantages of both polymer types block their individual usages as tissue scaffolds efficiently. Therefore, the idea of usage of natural and synthetic polymers together as a single 3D hybrid scaffold which has the advantages of both and the disadvantages of none has been entered to the literature. On the other hand, even though these hybrid structures support the cell adhesion and/or proliferation, various surface modification techniques applied to the surfaces of them to create topographical changes on the surfaces and to obtain reactive functional groups required for the immobilization of biomolecules, especially on the surfaces of synthetic polymers in order to improve cell adhesion and proliferation. In a study presented here, to improve the surface functionality and topography of the layer by layer electrospun 3D poly-epsilon-caprolactone/chitosan/poly-epsilon-caprolactone hybrid tissue scaffolds by using atmospheric pressure plasma method, thus to improve cell adhesion and proliferation of these tissue scaffolds were aimed. The formation/creation of the functional hydroxyl and amine groups and topographical changes on the surfaces of scaffolds were realized by using two different atmospheric pressure plasma systems (nozzle type and dielectric barrier discharge (DBD) type) carried out under different gas medium (air, Ar+O2, Ar+N2). The plasma modification time and distance for the nozzle type plasma system as well as the plasma modification time and the gas flow rate for DBD type plasma system were optimized with monitoring the changes in surface hydrophilicity by using contact angle measurements. The topographical and chemical characterizations of these modified biomaterials’ surfaces were carried out with SEM and ESCA, respectively. The results showed that the atmospheric pressure plasma modifications carried out with both nozzle type plasma and DBD plasma caused topographical and functionality changes on the surfaces of the layer by layer electrospun tissue scaffolds. However, the shelf life studies indicated that the hydrophilicity introduced to the surfaces was mainly because of the functionality changes. Therefore, according to the optimized results, samples treated with nozzle type air plasma modification applied for 9 minutes from a distance of 17 cm and Ar+O2 DBD plasma modification applied for 1 minute under 70 cm3/min O2 flow rate were found to have the highest hydrophilicity compared to pristine samples.

Keywords: biomaterial, chitosan, hybrid, plasma

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1326 Self-Assembling Layered Double Hydroxide Nanosheets on β-FeOOH Nanorods for Reducing Fire Hazards of Epoxy Resin

Authors: Wei Wang, Yuan Hu

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Epoxy resins (EP), one of the most important thermosetting polymers, is widely applied in various fields due to its desirable properties, such as excellent electrical insulation, low shrinkage, outstanding mechanical stiffness, satisfactory adhesion and solvent resistance. However, like most of the polymeric materials, EP has the fatal drawbacks including inherent flammability and high yield of toxic smoke, which restricts its application in the fields requiring fire safety. So, it is still a challenge and an interesting subject to develop new flame retardants which can not only remarkably improve the flame retardancy, but also render modified resins low toxic gases generation. In recent work, polymer nanocomposites based on nanohybrids that contain two or more kinds of nanofillers have drawn intensive interest, which can realize performance enhancements. The realization of previous hybrids of carbon nanotubes (CNTs) and molybdenum disulfide provides us a novel route to decorate layered double hydroxide (LDH) nanosheets on the surface of β-FeOOH nanorods; the deposited LDH nanosheets can fill the network and promote the work efficiency of β-FeOOH nanorods. Moreover, the synergistic effects between LDH and β-FeOOH can be anticipated to have potential applications in reducing fire hazards of EP composites for the combination of condense-phase and gas-phase mechanism. As reported, β-FeOOH nanorods can act as a core to prepare hybrid nanostructures combining with other nanoparticles through electrostatic attraction through layer-by-layer assembly technique. In this work, LDH nanosheets wrapped β-FeOOH nanorods (LDH-β-FeOOH) hybrids was synthesized by a facile method, with the purpose of combining the characteristics of one dimension (1D) and two dimension (2D), to improve the fire resistance of epoxy resin. The hybrids showed a well dispersion in EP matrix and had no obvious aggregation. Thermogravimetric analysis and cone calorimeter tests confirmed that LDH-β-FeOOH hybrids into EP matrix with a loading of 3% could obviously improve the fire safety of EP composites. The plausible flame retardancy mechanism was explored by thermogravimetric infrared (TG-IR) and X-ray photoelectron spectroscopy. The reasons were concluded: condense-phase and gas-phase. Nanofillers were transferred to the surface of matrix during combustion, which could not only shield EP matrix from external radiation and heat feedback from the fire zone, but also efficiently retard transport of oxygen and flammable pyrolysis.

Keywords: fire hazards, toxic gases, self-assembly, epoxy

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1325 Totally Implantable Venous Access Device for Long Term Parenteral Nutrition in a Patient with High Output Enterocutaneous Fistula Due to Advanced Malignancy

Authors: Puneet Goyal, Aarti Agarwal

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Background and Objective: Nutritional support is an integral part of palliative care of advanced non-resectable abdominal malignancy patients, though is frequently neglected aspect. Non-Healing high output Entero-cutaneous fistulas sometimes require long term parenteral nutrition, to take care of catabolism and replacement of nutrients. We present a case of inoperable pancreatic malignancy with high output entero-cutaneous fistula, which was provided parenteral nutritional support with the use of Totally Implantable Venous Access Device (TIVAD). Method and Results: 55 year old man diagnosed with carcinoma pancreas had developed high entero-cutaneous fistula. His tumor was found to be inoperable and was on total parenteral nutrition through routine central line. This line was difficult to maintain as he required it for a long term TPN. He was planned to undergo Totally Implantable Venous Access Device (TIVAD) implantation. 8Fr single lumen catheter with Groshong non-return Valve (Bard Access Systems, Inc. USA) was inserted through right internal jugular vein, under fluoroscopic guidance. The catheter was tunneled subcutaneously and brought towards infraclavicular pocket, cut at appropriate length and connected to port and locked. Port was sutured in floor of pocket. Free flow of blood aspirated, flushed with heparinized saline. There was no kink observed in entire length of catheter under fluoroscopy. Skin over infraclavicular pocket was sutured. Long term catheter care and associated risks were explained to patient and relatives. Patient continued to receive total parenteral nutrition as well as other supportive therapy though TIVAD for next 6 weeks, till his demise. Conclusion: TIVADs are standard of care for long term venous access solutions in cancer patients requiring chemotherapy. In this case, we extended its use for providing parenteral nutrition and other supportive therapy. TIVADs can be implanted in advanced cancer patients for providing venous access solution required for various palliative treatments and medications. This will help in improving quality of life and satisfaction amongst terminally ill cancer patients.

Keywords: parenteral nutrition, totally implantable venous access device, long term venous access, interventions in anesthesiology

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1324 Prevalence and Intensity of Soil Transmitted Helminth Infections among the School Children in the State of Uttar Pradesh, India

Authors: Prasanta Saini, Junaid Jibran Jawed, Subrata Majumdar

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Infections caused by soil-transmitted helminths (STH) are the major problem in all the nations of the world. The major focus of STH research is to study the prevalence of three major helminths, such as Ascaris, Trituris and hookworm. Here we are reporting the prevalence and intensity of the STH in the school children of the state of Uttar Pradesh, India. The aim of the study is to assess the prevalence and risk factors of STH infection among the school children, aged between 5-10 years in 27 districts randomly selected districts with covering nine agro-climatic zones of Uttar Pradesh, India. For this cross-sectional survey, we have selected the populations of government primary school going children in Uttar Pradesh. The sampling was performed in the nine different agro-climatic zones. Every individual of the study populations filled their daily information in the questioner's form and then the sample was collected and processed by kato-katz methods by following the guidelines of WHO. In this method, the sampling was performed in total of 6421 populations. A total of 6,421 children from 130 schools were surveyed. Infection with any soil-transmitted helminths was detected among 4,578 children with an overall prevalence of 75.6% (95% CI: 65.3-83.6). Among the 6421 population, the prevalence of Ascaris is 69.6% (95% CL 57.97-79.11), hookworm is 22.7% (95%CL 19.3-26.3) and Trichuris sp is 4.6% (95% CL 0.8-21.6), so the predicted prevalence map indicates that the STH infection was hyperendemic in this state. The findings of our survey in 130 schools covering 9 agro-climatic with one or more soil transmitted helminths. Majority of STH infections were of light intensity. STH infection was hyper-endemic in entire state, except three zones in western Uttar Pradesh. High prevalence ( > 75%) in all age groups also indicate little impact of existing deworming initiatives, including those among pre-school aged children. WHO recommends annual treatment in areas where STH prevalence is between 20% and 50%, and, a bi-annual treatment in areas with prevalence rates of over 50%. In view of high prevalence of STH infection in Uttar Pradesh, it is strongly recommended to initiate a deworming programme for school children in the state. Although our survey was among primary school children, high prevalence among children aged 4-6 years also indicates the need to strengthen the existing deworming programs for pre-school children. Extending the benefits of deworming to pre-school children through deworming in Anganwadi schools would further reduce to decrease the load of infection in community. As a long-term solution for control STH infection, it is also necessary to improve the sanitation levels in the area, as majority of the houses did not have latrines and most of the children were defecating in open fields, a factor that was found to be significantly associated with STH infection.

Keywords: prevalence, school going children, soil transmitted helminthes, Uttar Pradesh-India

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1323 Impact of Climate Change on Flow Regime in Himalayan Basins, Nepal

Authors: Tirtha Raj Adhikari, Lochan Prasad Devkota

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This research studied the hydrological regime of three glacierized river basins in Khumbu, Langtang and Annapurna regions of Nepal using the Hydraologiska Byrans Vattenbalansavde (HBV), HVB-light 3.0 model. Future scenario of discharge is also studied using downscaled climate data derived from statistical downscaling method. General Circulation Models (GCMs) successfully simulate future climate variability and climate change on a global scale; however, poor spatial resolution constrains their application for impact studies at a regional or a local level. The dynamically downscaled precipitation and temperature data from Coupled Global Circulation Model 3 (CGCM3) was used for the climate projection, under A2 and A1B SRES scenarios. In addition, the observed historical temperature, precipitation and discharge data were collected from 14 different hydro-metrological locations for the implementation of this study, which include watershed and hydro-meteorological characteristics, trends analysis and water balance computation. The simulated precipitation and temperature were corrected for bias before implementing in the HVB-light 3.0 conceptual rainfall-runoff model to predict the flow regime, in which Groups Algorithms Programming (GAP) optimization approach and then calibration were used to obtain several parameter sets which were finally reproduced as observed stream flow. Except in summer, the analysis showed that the increasing trends in annual as well as seasonal precipitations during the period 2001 - 2060 for both A2 and A1B scenarios over three basins under investigation. In these river basins, the model projected warmer days in every seasons of entire period from 2001 to 2060 for both A1B and A2 scenarios. These warming trends are higher in maximum than in minimum temperatures throughout the year, indicating increasing trend of daily temperature range due to recent global warming phenomenon. Furthermore, there are decreasing trends in summer discharge in Langtang Khola (Langtang region) which is increasing in Modi Khola (Annapurna region) as well as Dudh Koshi (Khumbu region) river basin. The flow regime is more pronounced during later parts of the future decades than during earlier parts in all basins. The annual water surplus of 1419 mm, 177 mm and 49 mm are observed in Annapurna, Langtang and Khumbu region, respectively.

Keywords: temperature, precipitation, water discharge, water balance, global warming

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1322 Enhancement of Fracture Toughness for Low-Temperature Applications in Mild Steel Weldments

Authors: Manjinder Singh, Jasvinder Singh

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Existing theories of Titanic/Liberty ship, Sydney bridge accidents and practical experience generated an interest in developing weldments those has high toughness under sub-zero temperature conditions. The purpose was to protect the joint from undergoing DBT (Ductile to brittle transition), when ambient temperature reach sub-zero levels. Metallurgical improvement such as low carbonization or addition of deoxidization elements like Mn and Si was effective to prevent fracture in weldments (crack) at low temperature. In the present research, an attempt has been made to investigate the reason behind ductile to brittle transition of mild steel weldments when subjected to sub-zero temperatures and method of its mitigation. Nickel is added to weldments using manual metal arc welding (MMAW) preventing the DBT, but progressive reduction in charpy impact values as temperature is lowered. The variation in toughness with respect to nickel content being added to the weld pool is analyzed quantitatively to evaluate the rise in toughness value with increasing nickel amount. The impact performance of welded specimens was evaluated by Charpy V-notch impact tests at various temperatures (20 °C, 0 °C, -20 °C, -40 °C, -60 °C). Notch is made in the weldments, as notch sensitive failure is particularly likely to occur at zones of high stress concentration caused by a notch. Then the effect of nickel to weldments is investigated at various temperatures was studied by mechanical and metallurgical tests. It was noted that a large gain in impact toughness could be achieved by adding nickel content. The highest yield strength (462J) in combination with good impact toughness (over 220J at – 60 °C) was achieved with an alloying content of 16 wt. %nickel. Based on metallurgical behavior it was concluded that the weld metals solidify as austenite with increase in nickel. The microstructure was characterized using optical and high resolution SEM (scanning electron microscopy). At inter-dendritic regions mainly martensite was found. In dendrite core regions of the low carbon weld metals a mixture of upper bainite, lower bainite and a novel constituent coalesced bainite formed. Coalesced bainite was characterized by large bainitic ferrite grains with cementite precipitates and is believed to form when the bainite and martensite start temperatures are close to each other. Mechanical properties could be rationalized in terms of micro structural constituents as a function of nickel content.

Keywords: MMAW, Toughness, DBT, Notch, SEM, Coalesced bainite

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1321 Optical Assessment of Marginal Sealing Performance around Restorations Using Swept-Source Optical Coherence Tomography

Authors: Rima Zakzouk, Yasushi Shimada, Yasunori Sumi, Junji Tagami

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Background and purpose: The resin composite has become the main material for the restorations of caries in recent years due to aesthetic characteristics, especially with the development of the adhesive techniques. The quality of adhesion to tooth structures is depending on an exchange process between inorganic tooth material and synthetic resin and a micromechanical retention promoted by resin infiltration in partially demineralized dentin. Optical coherence tomography (OCT) is a noninvasive diagnostic method for obtaining cross-sectional images that produce high-resolution of the biological tissue at the micron scale. The aim of this study was to evaluate the gap formation at adhesive/tooth interface of two-step self-etch adhesives that are preceded with or without phosphoric acid pre-etching in different regions of teeth using SS-OCT. Materials and methods: Round tapered cavities (2×2 mm) were prepared in cervical part of bovine incisors teeth and divided into 2 groups (n=10): first group self-etch adhesive (Clearfil SE Bond) was applied for SE group and second group treated with acid etching before applying the self-etch adhesive for PA group. Subsequently, both groups were restored with Estelite Flow Quick Flowable Composite Resin and observed under OCT. Following 5000 thermal cycles, the same section was obtained again for each cavity using OCT at 1310-nm wavelength. Scanning was repeated after two months to monitor the gap progress. Then the gap length was measured using image analysis software, and the statistics analysis were done between both groups using SPSS software. After that, the cavities were sectioned and observed under Confocal Laser Scanning Microscope (CLSM) to confirm the result of OCT. Results: Gaps formed at the bottom of the cavity was longer than the gap formed at the margin and dento-enamel junction in both groups. On the other hand, pre-etching treatment led to damage the DEJ regions creating longer gap. After 2 months the results showed almost progress in the gap length significantly at the bottom regions in both groups. In conclusions, phosphoric acid etching treatment did not reduce the gap lrngth in most regions of the cavity. Significance: The bottom region of tooth was more exposed to gap formation than margin and DEJ regions, The DEJ damaged with phosphoric acid treatment.

Keywords: optical coherence tomography, self-etch adhesives, bottom, dento enamel junction

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1320 Efficacy of Ergonomics Ankle Support on Squatting Pushing Skills during the Second Stage of Labor

Authors: Yu-Ching Lin, Meei-Ling Gau, Ghi-Hwei Kao, Hung-Chang Lee

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Objective: To compare the pushing experiences and birth outcomes of three different pushing positions during the second stage of labor. The three positions were: semi-recumbent, squatting, and squatting with the aid of ergonomically designed ankle supports. Methods: A randomized controlled trial was conducted at a regional teaching hospital in northern Taiwan. Data were collected from 168 primiparous women in their 38th to 42nd gestational week. None of the participants received epidural analgesia during labor and all were free of pregnancy and labor-related complications. Intervention: During labor, after full cervical dilation and when the fetal head had descended to at least the +1 station and had turned to the occiput anterior position, the experimental group was asked to push in the squatting position while wearing the ergonomically designed ankle supports; comparison group A was asked to push in the squatting position without the use of these supports; and comparison group B was asked to push in a standard semi-recumbent position. Measures: The participants completed a demographic and obstetrics datasheet, the Short Form McGill Pain Questionnaire (MPQ-SF), and the Labor Pushing Experience scale within 4-hours postpartum. Conclusion: In terms of delivery time, the duration between the start of pushing to crowning for the experimental group (squatting with ankle supports) averaged 25.52 minutes less (F =6.02, p< .05) than the time for comparison group B (semi-recumbent). Furthermore, the duration between the start of pushing to infant birth averaged 25.21 minutes less for the experimental group than for comparison group B (F =6.14, p< .05). Moreover, the experimental group had a lower average VAS pain score (5.05±3.22) than comparison group B and the average McGill pain score for the experimental group was lower than both comparison groups (F=18.12, p< .001). In summary, the participants in the group that delivered from a squatting position with ankle supports had better labor pushing experiences than their peers in the comparison groups. Results: In comparison to both unsupported squatting and semi-recumbent pushing, squatting with the aid of ergonomically designed ankle supports reduced pushing times, ameliorated labor pain, and improved the pushing experience. Clinical application and suggestion: The squatting with ankle-support intervention introduced in the present study may significantly reduce tiredness and difficulties in maintaining balance as well as increase pushing efficiency. Thus, this intervention may reduce the caring needs of women during the second stage of labor. This intervention may be introduced in midwifery education programs and in clinical practice as a method to improve the care of women during the second stage of labor.

Keywords: second stage of labor, pushing, squatting with ankle supports, squatting

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1319 Antenatal Monitoring of Pre-Eclampsia in a Low Resource Setting

Authors: Alina Rahim, Joanne Moffatt, Jessica Taylor, Joseph Hartland, Tamer Abdelrazik

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Background: In 2011, 15% of maternal deaths in Uganda were due to hypertensive disorders (pre-eclampsia and eclampsia). The majority of these deaths are avoidable with optimum antenatal care. The aim of the study was to evaluate how antenatal monitoring of pre-eclampsia was carried out in a low resource setting and to identify barriers to best practice as recommended by the World Health Organisation (WHO) as part of a 4th year medical student External Student Selected component field trip. Method: Women admitted to hospital with pre-eclampsia in rural Uganda (Villa Maria and Kitovu Hospitals) over a year-long period were identified using the maternity register and antenatal record book. It was not possible to obtain notes for all cases identified on the maternity register. Therefore a total of thirty sets of notes were reviewed. The management was recorded and compared to Ugandan National Guidelines and WHO recommendations. Additional qualitative information on routine practice was established by interviewing staff members from the obstetric and midwifery teams. Results: From the records available, all patients in this sample were managed according to WHO recommendations during labour. The rate of Caesarean section as a mode of delivery was noted to be high in this group of patients; 56% at Villa Maria and 46% at Kitovu. Antenatally two WHO recommendations were not routinely met: aspirin prophylaxis and calcium supplementation. This was due to lack of resources, and lack of attendance at antenatal clinic leading to poor detection of high-risk patients. Medical management of pre-eclampsia varied between individual patients, overall 93.3% complied with Ugandan national guidelines. Two patients were treated with diuretics, which is against WHO guidance. Discussion: Antenatal monitoring of pre-eclampsia is important in reducing severe morbidity, long-term disability and mortality amongst mothers and their babies 2 . Poor attendance at antenatal clinic is a barrier to healthcare in low-income countries. Increasing awareness of the importance of these visits for women should be encouraged. The majority of cases reviewed in this sample of women were treated according to Ugandan National Guidelines. It is recommended to commence the use of aspirin prophylaxis for women at high-risk of developing pre-eclampsia and the creation of detailed guidelines for Uganda which would allow for standardisation of care county-wide.

Keywords: antenatal monitoring, low resource setting, pre-eclampsia, Uganda

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1318 Assessment of Environmental Risk Factors of Railway Using Integrated ANP-DEMATEL Approach in Fuzzy Conditions

Authors: Mehrdad Abkenari, Mehmet Kunt, Mahdi Nourollahi

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Evaluating the environmental risk factors is a combination of analysis of transportation effects. Various definitions for risk can be found in different scientific sources. Each definition depends on a specific and particular perspective or dimension. The effects of potential risks present along the new proposed routes and existing infrastructures of large transportation projects like railways should be studied under comprehensive engineering frameworks. Despite various definitions provided for ‘risk’, all include a uniform concept. Two obvious aspects, loss and unreliability, have always been pointed in all definitions of this term. But, selection as the third aspect is usually implied and means how one notices it. Currently, conducting engineering studies on the environmental effects of railway projects have become obligatory according to the Environmental Assessment Act in developing countries. Considering the longitudinal nature of these projects and probable passage of railways through various ecosystems, scientific research on the environmental risk of these projects have become of great interest. Although many areas of expertise such as road construction in developing countries have not seriously committed to these studies yet, attention to these subjects in establishment or implementation of different systems have become an inseparable part of this wave of research. The present study used environmental risks identified and existing in previous studies and stations to use in next step. The second step proposes a new hybrid approach of analytical network process (ANP) and DEMATEL in fuzzy conditions for assessment of determined risks. Since evaluation of identified risks was not an easy touch, mesh structure was an appropriate approach for analyzing complex systems which were accordingly employed for problem description and modeling. Researchers faced the shortage of real space data and also due to the ambiguity of experts’ opinions and judgments, they were declared in language variables instead of numerical ones. Since fuzzy logic is appropriate for ambiguity and uncertainty, formulation of experts’ opinions in the form of fuzzy numbers seemed an appropriate approach. Fuzzy DEMATEL method was used to extract the relations between major and minor risk factors. Considering the internal relations of risk major factors and its sub-factors in the analysis of fuzzy network, the weight of risk’s main factors and sub-factors were determined. In general, findings of the present study, in which effective railway environmental risk indicators were theoretically identified and rated through the first usage of combined model of DEMATEL and fuzzy network analysis, indicate that environmental risks can be evaluated more accurately and also employed in railway projects.

Keywords: DEMATEL, ANP, fuzzy, risk

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1317 Experimental Investigation on the Effect of Prestress on the Dynamic Mechanical Properties of Conglomerate Based on 3D-SHPB System

Authors: Wei Jun, Liao Hualin, Wang Huajian, Chen Jingkai, Liang Hongjun, Liu Chuanfu

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Kuqa Piedmont is rich in oil and gas resources and has great development potential in Tarim Basin, China. However, there is a huge thick gravel layer developed with high content, wide distribution and variation in size of gravel, leading to the condition of strong heterogeneity. So that, the drill string is in a state of severe vibration and the drill bit is worn seriously while drilling, which greatly reduces the rock-breaking efficiency, and there is a complex load state of impact and three-dimensional in-situ stress acting on the rock in the bottom hole. The dynamic mechanical properties and the influencing factors of conglomerate, the main component of gravel layer, are the basis of engineering design and efficient rock breaking method and theoretical research. Limited by the previously experimental technique, there are few works published yet about conglomerate, especially rare in dynamic load. Based on this, a kind of 3D SHPB system, three-dimensional prestress, can be applied to simulate the in-situ stress characteristics, is adopted for the dynamic test of the conglomerate. The results show that the dynamic strength is higher than its static strength obviously, and while the three-dimensional prestress is 0 and the loading strain rate is 81.25~228.42 s-1, the true triaxial equivalent strength is 167.17~199.87 MPa, and the strong growth factor of dynamic and static is 1.61~1.92. And the higher the impact velocity, the greater the loading strain rate, the higher the dynamic strength and the greater the failure strain, which all increase linearly. There is a critical prestress in the impact direction and its vertical direction. In the impact direction, while the prestress is less than the critical one, the dynamic strength and the loading strain rate increase linearly; otherwise, the strength decreases slightly and the strain rate decreases rapidly. In the vertical direction of impact load, the strength increases and the strain rate decreases linearly before the critical prestress, after that, oppositely. The dynamic strength of the conglomerate can be reduced properly by reducing the amplitude of impact load so that the service life of rock-breaking tools can be prolonged while drilling in the stratum rich in gravel. The research has important reference significance for the speed-increasing technology and theoretical research while drilling in gravel layer.

Keywords: huge thick gravel layer, conglomerate, 3D SHPB, dynamic strength, the deformation characteristics, prestress

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1316 University Students' Perspectives on a Mindfulness-Based App for Weight, Weight Related Behaviors, and Stress: A Qualitative Focus Group Study

Authors: Lynnette Lyzwinski, Liam Caffery, Matthew Bambling, Sisira Edirippulige

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Introduction: A novel method of delivering mindfulness interventions for populations at risk of weight gain and stress-related eating, in particular, college students, is through mHealth. While there have been qualitative studies on mHealth for weight loss, there has not been a study on mHealth for weight loss using mindfulness that has explored student perspectives on a student centred mindfulness app and mindfulness-based text messages for eating and stress. Student perspective data will provide valuable information for creating a specific purpose weight management app and mindfulness-based text messages (for the Mindfulness App study). Methods: A qualitative focus group study was undertaken at St Lucia campus at the University of Queensland in March 2017. Students over the age of 18 were eligible to participate. Interviews were audiotaped and transcribed. One week following the focus group, students were sent sample mindfulness-based text messages based on their responses. Students provided written feedback via email. Data were analysed using N Vivo software. Results: The key themes in a future mindfulness-based app are a simple design interface, a focus on education/practical tips, and real-life practical exercises. Social media should be avoided. Key themes surrounding barriers include the perceived difficulty of mindfulness and a lack of proper guidance or knowledge. The mindfulness-based text messages were received positively. Key themes were creating messages with practical tips about how to be mindful and how to integrate mindful reflection of both one’s body and environment while on campus. Other themes including creating positive, inspirational messages. There was lack of agreement on the ideal timing for messages. Discussion: This is the first study that explored student perspectives on a mindfulness-app and mindfulness-based text messages for stress and weight management as a pre-trial study for the Mindfulness App trial for stress, lifestyle, and weight in students. It is important to consider maximizing the potential facilitators of use and minimize potential identified barriers when developing and designing a future mHealth mindfulness-based intervention tailored to the student consumer. Conclusion: Future mHealth studies may consider integrating mindfulness-based text messages in their interventions for weight and stress as this is a novel feature that appears to be acceptable for participants. The results of this focus group provide the basis to develop content for a specific purpose student app for weight management.

Keywords: mindfulness, college students, mHealth, weight loss

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1315 Additive Manufacturing of Microstructured Optical Waveguides Using Two-Photon Polymerization

Authors: Leonnel Mhuka

Abstract:

Background: The field of photonics has witnessed substantial growth, with an increasing demand for miniaturized and high-performance optical components. Microstructured optical waveguides have gained significant attention due to their ability to confine and manipulate light at the subwavelength scale. Conventional fabrication methods, however, face limitations in achieving intricate and customizable waveguide structures. Two-photon polymerization (TPP) emerges as a promising additive manufacturing technique, enabling the fabrication of complex 3D microstructures with submicron resolution. Objectives: This experiment aimed to utilize two-photon polymerization to fabricate microstructured optical waveguides with precise control over geometry and dimensions. The objective was to demonstrate the feasibility of TPP as an additive manufacturing method for producing functional waveguide devices with enhanced performance. Methods: A femtosecond laser system operating at a wavelength of 800 nm was employed for two-photon polymerization. A custom-designed CAD model of the microstructured waveguide was converted into G-code, which guided the laser focus through a photosensitive polymer material. The waveguide structures were fabricated using a layer-by-layer approach, with each layer formed by localized polymerization induced by non-linear absorption of the laser light. Characterization of the fabricated waveguides included optical microscopy, scanning electron microscopy, and optical transmission measurements. The optical properties, such as mode confinement and propagation losses, were evaluated to assess the performance of the additive manufactured waveguides. Conclusion: The experiment successfully demonstrated the additive manufacturing of microstructured optical waveguides using two-photon polymerization. Optical microscopy and scanning electron microscopy revealed the intricate 3D structures with submicron resolution. The measured optical transmission indicated efficient light propagation through the fabricated waveguides. The waveguides exhibited well-defined mode confinement and relatively low propagation losses, showcasing the potential of TPP-based additive manufacturing for photonics applications. The experiment highlighted the advantages of TPP in achieving high-resolution, customized, and functional microstructured optical waveguides. Conclusion: his experiment substantiates the viability of two-photon polymerization as an innovative additive manufacturing technique for producing complex microstructured optical waveguides. The successful fabrication and characterization of these waveguides open doors to further advancements in the field of photonics, enabling the development of high-performance integrated optical devices for various applications

Keywords: Additive Manufacturing, Microstructured Optical Waveguides, Two-Photon Polymerization, Photonics Applications

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1314 Hydrogen Induced Fatigue Crack Growth in Pipeline Steel API 5L X65: A Combined Experimental and Modelling Approach

Authors: H. M. Ferreira, H. Cockings, D. F. Gordon

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Climate change is driving a transition in the energy sector, with low-carbon energy sources such as hydrogen (H2) emerging as an alternative to fossil fuels. However, the successful implementation of a hydrogen economy requires an expansion of hydrogen production, transportation and storage capacity. The costs associated with this transition are high but can be partly mitigated by adapting the current oil and natural gas networks, such as pipeline, an important component of the hydrogen infrastructure, to transport pure or blended hydrogen. Steel pipelines are designed to withstand fatigue, one of the most common causes of pipeline failure. However, it is well established that some materials, such as steel, can fail prematurely in service when exposed to hydrogen-rich environments. Therefore, it is imperative to evaluate how defects (e.g. inclusions, dents, and pre-existing cracks) will interact with hydrogen under cyclic loading and, ultimately, to what extent hydrogen induced failure will limit the service conditions of steel pipelines. This presentation will explore how the exposure of API 5L X65 to a hydrogen-rich environment and cyclic loads will influence its susceptibility to hydrogen induced failure. That evaluation will be performed by a combination of several techniques such as hydrogen permeation testing (ISO 17081:2014), fatigue crack growth (FCG) testing (ISO 12108:2018 and AFGROW modelling), combined with microstructural and fractographic analysis. The development of a FCG test setup coupled with an electrochemical cell will be discussed, along with the advantages and challenges of measuring crack growth rates in electrolytic hydrogen environments. A detailed assessment of several electrolytic charging conditions will also be presented, using hydrogen permeation testing as a method to correlate the different charging settings to equivalent hydrogen concentrations and effective diffusivity coefficients, not only on the base material but also on the heat affected zone and weld of the pipelines. The experimental work is being complemented with AFGROW, a useful FCG modelling software that has helped inform testing parameters and which will also be developed to ultimately help industry experts perform structural integrity analysis and remnant life characterisation of pipeline steels under representative conditions. The results from this research will allow to conclude if there is an acceleration of the crack growth rate of API 5L X65 under the influence of a hydrogen-rich environment, an important aspect that needs to be rectified instandards and codes of practice on pipeline integrity evaluation and maintenance.

Keywords: AFGROW, electrolytic hydrogen charging, fatigue crack growth, hydrogen, pipeline, steel

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1313 A Dynamic Cardiac Single Photon Emission Computer Tomography Using Conventional Gamma Camera to Estimate Coronary Flow Reserve

Authors: Maria Sciammarella, Uttam M. Shrestha, Youngho Seo, Grant T. Gullberg, Elias H. Botvinick

Abstract:

Background: Myocardial perfusion imaging (MPI) is typically performed with static imaging protocols and visually assessed for perfusion defects based on the relative intensity distribution. Dynamic cardiac SPECT, on the other hand, is a new imaging technique that is based on time varying information of radiotracer distribution, which permits quantification of myocardial blood flow (MBF). In this abstract, we report a progress and current status of dynamic cardiac SPECT using conventional gamma camera (Infinia Hawkeye 4, GE Healthcare) for estimation of myocardial blood flow and coronary flow reserve. Methods: A group of patients who had high risk of coronary artery disease was enrolled to evaluate our methodology. A low-dose/high-dose rest/pharmacologic-induced-stress protocol was implemented. A standard rest and a standard stress radionuclide dose of ⁹⁹ᵐTc-tetrofosmin (140 keV) was administered. The dynamic SPECT data for each patient were reconstructed using the standard 4-dimensional maximum likelihood expectation maximization (ML-EM) algorithm. Acquired data were used to estimate the myocardial blood flow (MBF). The correspondence between flow values in the main coronary vasculature with myocardial segments defined by the standardized myocardial segmentation and nomenclature were derived. The coronary flow reserve, CFR, was defined as the ratio of stress to rest MBF values. CFR values estimated with SPECT were also validated with dynamic PET. Results: The range of territorial MBF in LAD, RCA, and LCX was 0.44 ml/min/g to 3.81 ml/min/g. The MBF between estimated with PET and SPECT in the group of independent cohort of 7 patients showed statistically significant correlation, r = 0.71 (p < 0.001). But the corresponding CFR correlation was moderate r = 0.39 yet statistically significant (p = 0.037). The mean stress MBF value was significantly lower for angiographically abnormal than that for the normal (Normal Mean MBF = 2.49 ± 0.61, Abnormal Mean MBF = 1.43 ± 0. 0.62, P < .001). Conclusions: The visually assessed image findings in clinical SPECT are subjective, and may not reflect direct physiologic measures of coronary lesion. The MBF and CFR measured with dynamic SPECT are fully objective and available only with the data generated from the dynamic SPECT method. A quantitative approach such as measuring CFR using dynamic SPECT imaging is a better mode of diagnosing CAD than visual assessment of stress and rest images from static SPECT images Coronary Flow Reserve.

Keywords: dynamic SPECT, clinical SPECT/CT, selective coronary angiograph, ⁹⁹ᵐTc-Tetrofosmin

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1312 Some Quality Parameters of Selected Maize Hybrids from Serbia for the Production of Starch, Bioethanol and Animal Feed

Authors: Marija Milašinović-Šeremešić, Valentina Semenčenko, Milica Radosavljević, Dušanka Terzić, Ljiljana Mojović, Ljubica Dokić

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Maize (Zea mays L.) is one of the most important cereal crops, and as such, one of the most significant naturally renewable carbohydrate raw materials for the production of energy and multitude of different products. The main goal of the present study was to investigate a suitability of selected maize hybrids of different genetic background produced in Maize Research Institute ‘Zemun Polje’, Belgrade, Serbia, for starch, bioethanol and animal feed production. All the hybrids are commercial and their detailed characterization is important for the expansion of their different uses. The starches were isolated by using a 100-g laboratory maize wet-milling procedure. Hydrolysis experiments were done in two steps (liquefaction with Termamyl SC, and saccharification with SAN Extra L). Starch hydrolysates obtained by the two-step hydrolysis of the corn flour starch were subjected to fermentation by S. cerevisiae var. ellipsoideus under semi-anaerobic conditions. The digestibility based on enzymatic solubility was performed by the Aufréré method. All investigated ZP maize hybrids had very different physical characteristics and chemical composition which could allow various possibilities of their use. The amount of hard (vitreous) and soft (floury) endosperm in kernel is considered one of the most important parameters that can influence the starch and bioethanol yields. Hybrids with a lower test weight and density and a greater proportion of soft endosperm fraction had a higher yield, recovery and purity of starch. Among the chemical composition parameters only starch content significantly affected the starch yield. Starch yields of studied maize hybrids ranged from 58.8% in ZP 633 to 69.0% in ZP 808. The lowest bioethanol yield of 7.25% w/w was obtained for hybrid ZP 611k and the highest by hybrid ZP 434 (8.96% w/w). A very significant correlation was determined between kernel starch content and the bioethanol yield, as well as volumetric productivity (48h) (r=0.66). Obtained results showed that the NDF, ADF and ADL contents in the whole maize plant of the observed ZP maize hybrids varied from 40.0% to 60.1%, 18.6% to 32.1%, and 1.4% to 3.1%, respectively. The difference in the digestibility of the dry matter of the whole plant among hybrids (ZP 735 and ZP 560) amounted to 18.1%. Moreover, the differences in the contents of the lignocelluloses fraction affected the differences in dry matter digestibility. From the results it can be concluded that genetic background of the selected maize hybrids plays an important part in estimation of the technological value of maize hybrids for various purposes. Obtained results are of an exceptional importance for the breeding programs and selection of potentially most suitable maize hybrids for starch, bioethanol and animal feed production.

Keywords: bioethanol, biomass quality, maize, starch

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1311 Structural and Binding Studies of Peptidyl-tRNA Hydrolase from Pseudomonas aeruginosa Provide a Platform for the Structure Based Inhibitor Design against Peptidyl-tRNA Hydrolase

Authors: Sujata Sharma, Avinash Singh, Lovely Gautam, Pradeep Sharma, Mau Sinha, Asha Bhushan, Punit Kaur, Tej P. Singh

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Peptidyl-tRNA hydrolase (Pth) Pth is an essential bacterial enzyme that catalyzes the release of free tRNA and peptide moeities from peptidyl tRNAs during stalling of protein synthesis. In order to design inhibitors of Pth from Pseudomonas aeruginosa (PaPth), we have determined the structures of PaPth in its native state and in the bound states with two compounds, amino acylate-tRNA analogue (AAtA) and 5-azacytidine (AZAC). The peptidyl-tRNA hydrolase gene from Pseudomonas aeruginosa was amplified by Phusion High-Fidelity DNA Polymerase using forward and reverse primers, respectively. The E. coliBL21 (λDE3) strain was used for expression of the recombinant peptidyl-tRNA hydrolase from Pseudomonas aeruginosa. The protein was purified using a Ni-NTA superflow column. The crystallization experiments were carried out using hanging drop vapour diffusion method. The crystals diffracted to 1.50 Å resolution. The data were processed using HKL-2000. The polypeptide chain of PaPth consists of 194 amino acid residues from Met1 to Ala194. The centrally located β-structure is surrounded by α-helices from all sides except the side that has entrance to the substrate binding site. The structures of the complexes of PaPth with AAtA and AZAC showed the ligands bound to PaPth in the substrate binding cleft and interacted with protein atoms extensively. The residues that formed intermolecular hydrogen bonds with the atoms of AAtA included Asn12, His22, Asn70, Gly113, Asn116, Ser148, and Glu161 of the symmetry related molecule. The amino acids that were involved in hydrogen bonded interactions in case of AZAC included, His22, Gly113, Asn116, and Ser148. As indicated by fittings of two ligands and the number of interactions made by them with protein atoms, AAtA appears to be a more compatible with the structure of the substrate binding cleft. However, there is a further scope to achieve a better stacking than that of O-tyrosyl moiety because it is not still ideally stacked. These observations about the interactions between the protein and ligands have provided the information about the mode of binding of ligands, nature and number of interactions. This information may be useful for the design of tight inhibitors of Pth enzymes.

Keywords: peptidyl tRNA hydrolase, Acinetobacter baumannii, Pth enzymes, O-tyrosyl

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1310 Quantification and Detection of Non-Sewer Water Infiltration and Inflow in Urban Sewer Systems

Authors: M. Beheshti, S. Saegrov, T. M. Muthanna

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Separated sewer systems are designed to transfer the wastewater from houses and industrial sections to wastewater treatment plants. Unwanted water in the sewer systems is a well-known problem, i.e. storm-water inflow is around 50% of the foul sewer, and groundwater infiltration to the sewer system can exceed 50% of total wastewater volume in deteriorated networks. Infiltration and inflow of non-sewer water (I/I) into sewer systems is unfavorable in separated sewer systems and can trigger overloading the system and reducing the efficiency of wastewater treatment plants. Moreover, I/I has negative economic, environmental, and social impacts on urban areas. Therefore, for having sustainable management of urban sewer systems, I/I of unwanted water into the urban sewer systems should be considered carefully and maintenance and rehabilitation plan should be implemented on these water infrastructural assets. This study presents a methodology to identify and quantify the level of I/I into the sewer system. Amount of I/I is evaluated by accurate flow measurement in separated sewer systems for specified isolated catchments in Trondheim city (Norway). Advanced information about the characteristics of I/I is gained by CCTV inspection of sewer pipelines with high I/I contribution. Achieving enhanced knowledge about the detection and localization of non-sewer water in foul sewer system during the wet and dry weather conditions will enable the possibility for finding the problem of sewer system and prioritizing them and taking decisions for rehabilitation and renewal planning in the long-term. Furthermore, preventive measures and optimization of sewer systems functionality and efficiency can be executed by maintenance of sewer system. In this way, the exploitation of sewer system can be improved by maintenance and rehabilitation of existing pipelines in a sustainable way by more practical cost-effective and environmental friendly way. This study is conducted on specified catchments with different properties in Trondheim city. Risvollan catchment is one of these catchments with a measuring station to investigate hydrological parameters through the year, which also has a good database. For assessing the infiltration in a separated sewer system, applying the flow rate measurement method can be utilized in obtaining a general view of the network condition from infiltration point of view. This study discusses commonly used and advanced methods of localizing and quantifying I/I in sewer systems. A combination of these methods give sewer operators the possibility to compare different techniques and obtain reliable and accurate I/I data which is vital for long-term rehabilitation plans.

Keywords: flow rate measurement, infiltration and inflow (I/I), non-sewer water, separated sewer systems, sustainable management

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1309 High Acid-Stable α-Amylase Production by Milk in Liquid Culture

Authors: Shohei Matsuo, Saki Mikai, Hiroshi Morita

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Objectives: Shochu is a popular Japanese distilled spirits. In the production of shochu, the filamentous fungus Aspergillus kawachii has traditionally been used. A. kawachii produces two types of starch hydrolytic enzymes, α-amylase (enzymatic liquefaction) and glucoamylase (enzymatic saccharification). Liquid culture system is a relatively easy microorganism to ferment with relatively low cost of production compared for solid culture. In liquid culture system, acid-unstable α-amylase (α-A) was produced abundantly, but, acid-stable α-amylase (Aα-A) was not produced. Since there is high enzyme productivity, most in shochu brewing have been adopted by a solid culture method. In this study, therefore, we investigated production of Aα-A in liquid culture system. Materials and methods: Microorganism Aspergillus kawachii NBRC 4308 was used. The mold was cultured at 30 °C for 7~14 d to allow formation of conidiospores on slant agar medium. Liquid Culture System: A. kawachii was cultured in a 100 ml of following altered SLS medium: 1.0 g of rice flour, 0.1 g of K2HPO4, 0.1 g of KCl, 0.6 g of tryptone, 0.05 g of MgSO4・7H2O, 0.001 g of FeSO4・7H2O, 0.0003 g of ZnSO4・7H2O, 0.021 g of CaCl2, 0.33 of citric acid (pH 3.0). The pH of the medium was adjusted to the designated value with 10 % HCl solution. The cultivation was shaking at 30 °C and 200 rpm for 72 h. It was filtered to obtain a crude enzyme solution. Aα-A assay: The crude enzyme solution was analyzed. An acid-stable α-amylase activity was carried out using an α-amylase assay kit (Kikkoman Corporation, Noda, Japan). It was conducted after adding 9 ml of 100 mM acetate buffer (pH 3.0) to 1 ml of the culture product supernatant and acid treatment at 37°C for 1 h. One unit of a-amylase activity was defined as the amount of enzyme that yielded 1 mmol of 2-chloro-4-nitrophenyl 6-azide-6-deoxy-b-maltopentaoside (CNP) per minute. Results and Conclusion: We experimented with co-culture of A. kawachii and lactobacillus in order to get control of pH in altered SLS medium. However, high production of acid-stable α-amylase was not obtained. We experimented with yoghurt or milk made an addition to liquid culture. The result indicated that high production of acid-stable α-amylase (964 U/g-substrate) was obtained when milk made an addition to liquid culture. Phosphate concentration in the liquid medium was a major cause of increased acid-stable α-amylase activity. In liquid culture, acid-stable α-amylase activity was enhanced by milk, but Fats and oils in the milk were oxidized. In addition, Tryptone is not approved as a food additive in Japan. Thus, alter SLS medium added to skim milk excepting for the fats and oils in the milk instead of tryptone. The result indicated that high production of acid-stable α-amylase was obtained with the same effect as milk.

Keywords: acid-stable α-amylase, liquid culture, milk, shochu

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1308 Phytoremediation of Hydrocarbon-Polluted Soils: Assess the Potentialities of Six Tropical Plant Species

Authors: Pulcherie Matsodoum Nguemte, Adrien Wanko Ngnien, Guy Valerie Djumyom Wafo, Ives Magloire Kengne Noumsi, Pierre Francois Djocgoue

Abstract:

The identification of plant species with the capacity to grow on hydrocarbon-polluted soils is an essential step for phytoremediation. In view of developing phytoremediation in Cameroon, floristic surveys have been conducted in 4 cities (Douala, Yaounde, Limbe, and Kribi). In each city, 13 hydrocarbon-polluted, as well as unpolluted sites (control), have been investigated using quadrat method. 106 species belonging to 76 genera and 30 families have been identified on hydrocarbon-polluted sites, unlike the control sites where floristic diversity was much higher (166 species contained in 125 genera and 50 families). Poaceae, Cyperaceae, Asteraceae and Amaranthaceae have higher taxonomic richness on polluted sites (16, 15,10 and 8 taxa, respectively). Shannon diversity index of the hydrocarbon-polluted sites (1.6 to 2.7 bits/ind.) were significantly lower than the control sites (2.7 to 3.2 bits/ind.). Based on a relative frequency > 10% and abundance > 7%, this study highlights more than ten plants predisposed to be effective in the cleaning-up attempts of soils contaminated by hydrocarbons. Based on the floristic indicators, 6 species (Eleusine indica (L.) Gaertn., Cynodon dactylon (L.) Pers., Alternanthera sessilis (L.) R. Br. ex DC †, Commelinpa benghalensis L., Cleome ciliata Schum. & Thonn. and Asystasia gangetica (L.) T. Anderson) were selected for a study to determine their capacity to remediate a soil contaminated with fuel oil (82.5 ml/ kg of soil). The experiments lasting 150 days takes into account three modalities - Tn: uncontaminated soils planted (6) To contaminated soils unplanted (3) and Tp: contaminated soil planted (18) – randomized arranged. 3 on 6 species (Eleusine indica, Cynodon dactylon, and Alternanthera sessilis) survived the climatic and soil conditions. E. indica presents a significantly higher growth rate for density and leaf area while C. dactylon had a significantly higher growth rate for stem size and leaf numbers. A. sessilis showed stunted growth and development throughout the experimental period. The species Eleusine indica (L.) Gaertn. and Cynodon dactylon (L.) Pers. can be qualified as polluo-tolerant plant species; polluo-tolerance being the ability of a species to survive and develop in the midst subject to extreme physical and chemical disturbances.

Keywords: Cameroon, cleaning-up, floristic surveys, phytoremediation

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1307 The Aromaticity of P-Substituted O-(N-Dialkyl)Aminomethylphenols

Authors: Khodzhaberdi Allaberdiev

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Aromaticity, one of the most important concepts in organic chemistry, has attracted considerable interest from both experimentalists and theoreticians. The geometry optimization of p-substituted o-(N-dialkyl)aminomethylphenols, o-DEAMPH XC₆ H₅CH ₂Y (X=p-OCH₃, CH₃, H, F, Cl, Br, COCH₃, COOCH₃, CHO, CN and NO₂, Y=o-N (C₂H₅)₂, o-DEAMPHs have been performed in the gas phase using the B3LYP/6-311+G(d,p) level. Aromaticities of the considered molecules were investigated using different indices included geometrical (HOMA and Bird), electronic (FLU, PDI and SA) magnetic (NICS(0), NICS(1) and NICS(1)zz indices. The linear dependencies were obtained between some aromaticity indices. The best correlation is observed between the Bird and PDI indices (R² =0.9240). However, not all types of indices or even different indices within the same type correlate well among each other. Surprisingly, for studied molecules in which geometrical and electronic cannot correctly give the aromaticity of ring, the magnetism based index successfully predicts the aromaticity of systems. 1H NMR spectra of compounds were obtained at B3LYP/6–311+G(d,p) level using the GIAO method. Excellent linear correlation (R²= 0.9996) between values the chemical shift of hydrogen atom obtained experimentally of 1H NMR and calculated using B3LYP/6–311+G(d,p) demonstrates a good assignment of the experimental values chemical shift to the calculated structures of o-DEAMPH. It is found that the best linear correlation with the Hammett substituent constants is observed for the NICS(1)zz index in comparison with the other indices: NICS(1)zz =-21.5552+1,1070 σp- (R²=0.9394). The presence intramolecular hydrogen bond in the studied molecules also revealed changes the aromatic character of substituted o-DEAMPHs. The HOMA index predicted for R=NO2 the reduction in the π-electron delocalization of 3.4% was about double that observed for p-nitrophenol. The influence intramolecular H-bonding on aromaticity of benzene ring in the ground state (S0) are described by equations between NICS(1)zz and H-bond energies: experimental, Eₑₓₚ, predicted IR spectroscopical, Eν and topological, EQTAIM with correlation coefficients R² =0.9666, R² =0.9028 and R² =0.8864, respectively. The NICS(1)zz index also correlates with usual descriptors of the hydrogen bond, while the other indices do not give any meaningful results. The influence of the intramolecular H-bonding formation on the aromaticity of some substituted o-DEAMPHs is criteria to consider the multidimensional character of aromaticity. The linear relationships as well as revealed between NICS(1)zz and both pyramidality nitrogen atom, ΣN(C₂H₅)₂ and dihedral angle, φ CAr – CAr -CCH₂ –N, to characterizing out-of-plane properties.These results demonstrated the nonplanar structure of o-DEAMPHs. Finally, when considering dependencies of NICS(1)zz, were excluded data for R=H, because the NICS(1) and NICS(1)zz values are the most negative for unsubstituted DEAMPH, indicating its highest aromaticity; that was not the case for NICS(0) index.

Keywords: aminomethylphenols, DFT, aromaticity, correlations

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1306 Ayurvastra: A Study on the Ancient Indian Textile for Healing

Authors: Reena Aggarwal

Abstract:

The use of textile chemicals in the various pre and post-textile manufacturing processes has made the textile industry conscious of its negative contribution to environmental pollution. Popular environmentally friendly fibers such as recycled polyester and organic cotton have been now increasingly used by fabrics and apparel manufacturers. However, after these textiles or the finished apparel are manufactured, they have to be dyed in the same chemical dyes that are harmful and toxic to the environment. Dyeing is a major area of concern for the environment as well as for people who have chemical sensitivities as it may cause nausea, breathing difficulties, seizures, etc. Ayurvastra or herbal medical textiles are one step ahead of the organic lifestyle, which supports the core concept of holistic well-being and also eliminates the impact of harmful chemicals and pesticides. There is a wide range of herbs that can be used not only for dyeing but also for providing medicinal properties to the textiles like antibacterial, antifungal, antiseptic, antidepressant and for treating insomnia, skin diseases, etc. The concept of herbal dyeing of fabric is to manifest herbal essence in every aspect of clothing, i.e., from production to end-use, additionally to eliminate the impact of harmful chemical dyes and chemicals which are known to result in problems like skin rashes, headache, trouble concentrating, nausea, diarrhea, fatigue, muscle and joint pain, dizziness, difficulty breathing, irregular heartbeat and seizures. Herbal dyeing or finishing on textiles will give an extra edge to the textiles as it adds an extra function to the fabric. The herbal extracts can be applied to the textiles by a simple process like the pad dry cure method and mainly acts on the human body through the skin for aiding in the treatment of disease or managing the medical condition through its herbal properties. This paper, therefore, delves into producing Ayurvastra, which is a perfect amalgamation of cloth and wellness. The aim of the paper is to design and create herbal disposable and non-disposable medical textile products acting mainly topically (through the skin) for providing medicinal properties/managing medical conditions. Keeping that in mind, a range of antifungal socks and antibacterial napkins treated with turmeric and aloe vera were developed, which are recommended for the treatment of fungal and bacterial infections, respectively. Both Herbal Antifungal socks and Antibacterial napkins have proved to be efficient enough in managing and treating fungal and bacterial infections of the skin, respectively.

Keywords: ayurvastra, ayurveda, herbal, pandemic, sustainable

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1305 Barrier Analysis of Sustainable Development of Small Towns: A Perspective of Southwest China

Authors: Yitian Ren, Liyin Shen, Tao Zhou, Xiao Li

Abstract:

The past urbanization process in China has brought out series of problems, the Chinese government has then positioned small towns in essential roles for implementing the strategy 'The National New-type Urbanization Plan (2014-2020)'. As the connector and transfer station of cities and countryside, small towns are important force to narrow the gap between urban and rural area, and to achieve the mission of new-type urbanization in China. The sustainable development of small towns plays crucial role because cities are not capable enough to absorb the surplus rural population. Nevertheless, there are various types of barriers hindering the sustainable development of small towns, which led to the limited development of small towns and has presented a bottleneck in Chinese urbanization process. Therefore, this paper makes deep understanding of these barriers, thus effective actions can be taken to address them. And this paper chooses the perspective of Southwest China (refers to Sichuan province, Yunnan province, Guizhou province, Chongqing Municipality City and Tibet Autonomous Region), cause the urbanization rate in Southwest China is far behind the average urbanization level of the nation and the number of small towns accounts for a great proportion in mainland China, also the characteristics of small towns in Southwest China are distinct. This paper investigates the barriers of sustainable development of small towns which located in Southwest China by using the content analysis method, combing with the field work and interviews in sample small towns, then identified and concludes 18 barriers into four dimensions, namely, institutional barriers, economic barriers, social barriers and ecological barriers. Based on the research above, questionnaire survey and data analysis are implemented, thus the key barriers hinder the sustainable development of small towns in Southwest China are identified by using fuzzy set theory, those barriers are, lack of independent financial power, lack of construction land index, financial channels limitation, single industrial structure, topography variety and complexity, which mainly belongs to institutional barriers and economic barriers. In conclusion part, policy suggestions are come up with to improve the politic and institutional environment of small town development, also the market mechanism are supposed to be introduced to the development process of small towns, which can effectively overcome the economic barriers, promote the sustainable development of small towns, accelerate the in-situ urbanization by absorbing peasants in nearby villages, and achieve the mission of new-type urbanization in China from the perspective of people-oriented.

Keywords: barrier analysis, sustainable development, small town, Southwest China

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1304 Control of Doxorubicin Release Rate from Magnetic PLGA Nanoparticles Using a Non-Permanent Magnetic Field

Authors: Inês N. Peça , A. Bicho, Rui Gardner, M. Margarida Cardoso

Abstract:

Inorganic/organic nanocomplexes offer tremendous scope for future biomedical applications, including imaging, disease diagnosis and drug delivery. The combination of Fe3O4 with biocompatible polymers to produce smart drug delivery systems for use in pharmaceutical formulation present a powerful tool to target anti-cancer drugs to specific tumor sites through the application of an external magnetic field. In the present study, we focused on the evaluation of the effect of the magnetic field application time on the rate of drug release from iron oxide polymeric nanoparticles. Doxorubicin, an anticancer drug, was selected as the model drug loaded into the nanoparticles. Nanoparticles composed of poly(d-lactide-co-glycolide (PLGA), a biocompatible polymer already approved by FDA, containing iron oxide nanoparticles (MNP) for magnetic targeting and doxorubicin (DOX) were synthesized by the o/w solvent extraction/evaporation method and characterized by scanning electron microscopy (SEM), by dynamic light scattering (DLS), by inductively coupled plasma-atomic emission spectrometry and by Fourier transformed infrared spectroscopy. The produced particles yielded smooth surfaces and spherical shapes exhibiting a size between 400 and 600 nm. The effect of the magnetic doxorubicin loaded PLGA nanoparticles produced on cell viability was investigated in mammalian CHO cell cultures. The results showed that unloaded magnetic PLGA nanoparticles were nontoxic while the magnetic particles without polymeric coating show a high level of toxicity. Concerning the therapeutic activity doxorubicin loaded magnetic particles cause a remarkable enhancement of the cell inhibition rates compared to their non-magnetic counterpart. In vitro drug release studies performed under a non-permanent magnetic field show that the application time and the on/off cycle duration have a great influence with respect to the final amount and to the rate of drug release. In order to determine the mechanism of drug release, the data obtained from the release curves were fitted to the semi-empirical equation of the the Korsmeyer-Peppas model that may be used to describe the Fickian and non-Fickian release behaviour. Doxorubicin release mechanism has shown to be governed mainly by Fickian diffusion. The results obtained show that the rate of drug release from the produced magnetic nanoparticles can be modulated through the magnetic field time application.

Keywords: drug delivery, magnetic nanoparticles, PLGA nanoparticles, controlled release rate

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1303 Measurement of in-situ Horizontal Root Tensile Strength of Herbaceous Vegetation for Improved Evaluation of Slope Stability in the Alps

Authors: Michael T. Lobmann, Camilla Wellstein, Stefan Zerbe

Abstract:

Vegetation plays an important role for the stabilization of slopes against erosion processes, such as shallow erosion and landslides. Plant roots reinforce the soil, increase soil cohesion and often cross possible shear planes. Hence, plant roots reduce the risk of slope failure. Generally, shrub and tree roots penetrate deeper into the soil vertically, while roots of forbs and grasses are concentrated horizontally in the topsoil and organic layer. Therefore, shrubs and trees have a higher potential for stabilization of slopes with deep soil layers than forbs and grasses. Consequently, research mainly focused on the vertical root effects of shrubs and trees. Nevertheless, a better understanding of the stabilizing effects of grasses and forbs is needed for better evaluation of the stability of natural and artificial slopes with herbaceous vegetation. Despite the importance of vertical root effects, field observations indicate that horizontal root effects also play an important role for slope stabilization. Not only forbs and grasses, but also some shrubs and trees form tight horizontal networks of fine and coarse roots and rhizomes in the topsoil. These root networks increase soil cohesion and horizontal tensile strength. Available methods for physical measurements, such as shear-box tests, pullout tests and singular root tensile strength measurement can only provide a detailed picture of vertical effects of roots on slope stabilization. However, the assessment of horizontal root effects is largely limited to computer modeling. Here, a method for measurement of in-situ cumulative horizontal root tensile strength is presented. A traction machine was developed that allows fixation of rectangular grass sods (max. 30x60cm) on the short ends with a 30x30cm measurement zone in the middle. On two alpine grass slopes in South Tyrol (northern Italy), 30x60cm grass sods were cut out (max. depth 20cm). Grass sods were pulled apart measuring the horizontal tensile strength over 30cm width over the time. The horizontal tensile strength of the sods was measured and compared for different soil depths, hydrological conditions, and root physiological properties. The results improve our understanding of horizontal root effects on slope stabilization and can be used for improved evaluation of grass slope stability.

Keywords: grassland, horizontal root effect, landslide, mountain, pasture, shallow erosion

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1302 Stress Corrosion Crackings Test of Candidate Materials in Support of the Development of the European Small Modular Supercritical Water Cooled Rector Concept

Authors: Radek Novotny, Michal Novak, Daniela Marusakova, Monika Sipova, Hugo Fuentes, Peter Borst

Abstract:

This research has been conducted within the European HORIZON 2020 project ECC-SMART. The main objective is to assess whether it is feasible to design and develop a small modular reactor (SMR) that would be cooled by supercritical water (SCW). One of the main objectives for material research concerns the corrosion of the candidate cladding materials. The experimental part has been conducted in support of the qualification procedure of the future SCW-SMR constructional materials. The last objective was to identify the gaps in current norms and guidelines. Apart from corrosion, resistance testing of candidate materials stresses corrosion cracking susceptibility tests have been performed in supercritical water. This paper describes part of these tests, in particular, those slow strain rate tensile loading applied for tangential ring shape specimens of two candidate materials, Alloy 800H and 310S stainless steel. These ring tensile tests are one the methods used for tensile testing of nuclear cladding. Here full circular heads with dimensions roughly equal to the inner diameter of the sample and the gage sections are placed in the parallel direction to the applied load. Slow strain rate tensile tests have been conducted in 380 or 500oC supercritical water applying two different elongation rates, 1x10-6 and 1x10-7 s-1. The effect of temperature and dissolved oxygen content on the SCC susceptibility of Alloy 800H and 310S stainless steel was investigated when two different temperatures and concentrations of dissolved oxygen were applied in supercritical water. The post-fracture analysis includes fractographic analysis of the fracture surfaces using SEM as well as cross-sectional analysis on the occurrence of secondary cracks. Assessment of the effect of environment and dissolved oxygen content was by comparing to the results of the reference tests performed in air and N2 gas overpressure. The effect of high temperature on creep and its role in the initiation of SCC was assessed as well. It has been concluded that the applied test method could be very useful for the investigation of stress corrosion cracking susceptibility of candidate cladding materials in supercritical water.

Keywords: stress corrosion cracking, ring tensile tests, super-critical water, alloy 800H, 310S stainless steel

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