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Authors: Irene Capecchi, Tommaso Borghini, Iacopo Bernetti

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One of the most common pieces of equipment still used today for pruning, felling, and processing trees is the chainsaw in forestry. However, chainsaw use highlights dangers and one of the highest rates of accidents in both professional and non-professional work. Felling is proportionally the most dangerous phase, both in severity and frequency, because of the risk of being hit by the plant the operator wants to cut down. To avoid this, a correct sequence of chainsaw cuts must be taught concerning the different conditions of the tree. Virtual reality (VR) makes it possible to virtually simulate chainsaw use without danger of injury. The limitations of the existing applications are as follow. The existing platforms are not symmetrical collaborative because the trainee is only in virtual reality, and the trainer can only see the virtual environment on a laptop or PC, and this results in an inefficient teacher-learner relationship. Therefore, most applications only involve the use of a virtual chainsaw, and the trainee thus cannot feel the real weight and inertia of a real chainsaw. Finally, existing applications simulate only a few cases of tree felling. The objectives of this research were to implement and test a symmetrical collaborative training application based on VR and mixed reality (MR) with the overlap between real and virtual chainsaws in MR. The research and training platform was developed for the Meta quest 2 head-mounted display. The research and training platform application is based on the Unity 3D engine, and Present Platform Interaction SDK (PPI-SDK) developed by Meta. PPI-SDK avoids the use of controllers and enables hand tracking and MR. With the combination of these two technologies, it was possible to overlay a virtual chainsaw with a real chainsaw in MR and synchronize their movements in VR. This ensures that the user feels the weight of the actual chainsaw, tightens the muscles, and performs the appropriate movements during the test allowing the user to learn the correct body posture. The chainsaw works only if the right sequence of cuts is made to felling the tree. Contact detection is done by Unity's physics system, which allows the interaction of objects that simulate real-world behavior. Each cut of the chainsaw is defined by a so-called collider, and the felling of the tree can only occur if the colliders are activated in the right order simulating a safe technique felling. In this way, the user can learn how to use the chainsaw safely. The system is also multiplayer, so the student and the instructor can experience VR together in a symmetrical and collaborative way. The platform simulates the following tree-felling situations with safe techniques: cutting the tree tilted forward, cutting the medium-sized tree tilted backward, cutting the large tree tilted backward, sectioning the trunk on the ground, and cutting branches. The application is being evaluated on a sample of university students through a special questionnaire. The results are expected to test both the increase in learning compared to a theoretical lecture and the immersive and telepresence of the platform.

Keywords: chainsaw, collaborative symmetric virtual reality, mixed reality, operator training

Procedia PDF Downloads 83

Authors: Chen Chuanzhi, Guo Yunyun

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The large linear array feeding parabolic cylindrical antenna of the satellite has the ability of large-area line focusing, multi-directional beam clusters simultaneously in a certain azimuth plane and elevation plane, corresponding quickly to different orientations and different directions in a wide frequency range, dual aiming of frequency and direction, and combining space power. Therefore, the large-diameter parabolic cylindrical antenna has become one of the new development directions of spaceborne antennas. Limited by the size of the rocked fairing, the large-diameter spaceborne antenna is required to be small mass and have a deployment function. After being orbited, the antenna can be deployed by expanding and be stabilized. However, few types of structures can be used to construct large cylindrical shell structures in existing structures, which greatly limits the development and application of such antennas. Aiming at high structural efficiency, the geometrical characteristics of parabolic cylinders and mechanism topological mapping law to the expandable truss are studied, and the basic configuration of deployable truss with cylindrical shell is structured. Then a modular truss parabolic cylindrical antenna is designed in this paper. The antenna has the characteristics of stable structure, high precision of reflecting surface formation, controllable motion process, high storage rate, and lightweight, etc. On the basis of the overall configuration comprehensive theory and optimization method, the structural stiffness of the modular truss parabolic cylindrical antenna is improved. And the bearing density and impact resistance of support structure are improved based on the internal tension optimal distribution method of reflector forming. Finally, a truss-type cylindrical deployable support structure with high constriction-deployment ratio, high stiffness, controllable deployment, and low mass is successfully developed, laying the foundation for the application of large-diameter parabolic cylindrical antennas in satellite antennas.

Keywords: linear array feed antenna, truss type, parabolic cylindrical antenna, spaceborne antenna

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Authors: Luca Indovina, Carmela Coppola, Carlo Altucci, Riccardo Barberi, Rocco Romano

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In this paper a real court case, held in Italy at the Court of Nola, in which a correct physical description, conducted with both a Monte Carlo and biophysical analysis, would have been sufficient to arrive at conclusions confirmed by documentary evidence, is considered. This will be an example of how forensic physics can be useful in confirming documentary evidence in order to reach hardly questionable conclusions. This was a libel trial in which the defendant, Mr. DS (Defendant for Slander), had falsely accused one of his neighbors, Mr. OP (Offended Person), of having caused him some damages. The damages would have been caused by an external plaster piece that would have detached from the neighbor’s property and would have hit Mr DS while he was in his garden, much more than a meter far away from the facade of the building from which the plaster piece would have detached. In the trial, Mr. DS claimed to have suffered a scratch on his forehead, but he never showed the plaster that had hit him, nor was able to tell from where the plaster would have arrived. Furthermore, Mr. DS presented a medical certificate with a diagnosis of contusion of the cerebral cortex. On the contrary, the images of Mr. OP’s security cameras do not show any movement in the garden of Mr. DS in a long interval of time (about 2 hours) around the time of the alleged accident, nor do they show any people entering or coming out from the house of Mr. DS in the same interval of time. Biophysical analysis shows that both the diagnosis of the medical certificate and the wound declared by the defendant, already in conflict with each other, are not compatible with the fall of external plaster pieces too small to be found. The wind was at a level 1 of the Beaufort scale, that is, unable to raise even dust (level 4 of the Beaufort scale). Therefore, the motion of the plaster pieces can be described as a projectile motion, whereas collisions with the building cornice can be treated using Newtons law of coefficients of restitution. Numerous numerical Monte Carlo simulations show that the pieces of plaster would not have been able to reach even the garden of Mr. DS, let alone a distance over 1.30 meters. Results agree with the documentary evidence (images of Mr. OP’s security cameras) that Mr. DS could not have been hit by plaster pieces coming from Mr. OP’s property.

Keywords: biophysics analysis, Monte Carlo simulations, Newton’s law of restitution, projectile motion

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Authors: Komal Vig, Syamala Soumyakrishnan, Yadav Baral

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Bypass surgery, using the autologous vein has been one of the most effective treatments for cardiovascular diseases (CVD). More recently tissue engineering including engineered vascular grafts to synthesize blood vessels is gaining usage. Dacron and ePTFE has been employed for vascular grafts, however, these does not work well for small diameter grafts (<6 mm) due to intimal hyperplasia and thrombosis. In the present study PTFE was treated with LTP to improve the endothelialization of intimal surface of graft. Scaffolds were also modified with polyvinylpyrrolidone coated silver nanoparticles (Ag-PVP) and the antimicrobial peptides, p753 and p359. Human umbilical vein endothelial cells (HUVEC) were plated on the developed scaffolds and cell proliferation was determined by the MTT assay. Cells attachment on scaffolds was visualized by microscopy. mRNA expressions levels of different cell markers were investigated using quantitative real-time PCR (qPCR). X ray photoelectron spectroscopic confirmed the introduction of oxygenated functionalities from LTP air plasma. Microscopic and MTT assays indicated increase in cell viability in LTP treated scaffolds. Gene expression studies shows enhanced expression of cell adhesion marker Integrin- α 5 gene after LTP treatment. The KB test displayed a zone of inhibition for Ag-PVP, p753 and p359 of 19mm, 14mm, and 12mm respectively. To determine toxicity of antimicrobial agents to cells, MTT Assay was performed using HEK293 cells. MTT Assay exhibited that Ag-PVP and the peptides were non-toxic to cells at 100μg/mL and 50μg/mL, respectively. Live/dead analysis and plate count of treated bacteria exhibited bacterial inhibition on develop scaffold compared to non-treated scaffold. SEM was performed to analyze the structural changes of bacteria after treatment with antimicrobial agents. Gene expression studies were conducted on RNA from bacteria treated with Ag-PVP and peptides using qRT-PCR. Based on our initial results, more scaffolds alternatives will be developed and investigated for cell growth and vascularization studies.

Keywords: low temperature plasma, vascular graft, HUVEC cells, antimicrobial

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Authors: Goldie Lynn Diaz, Ma. Teresa Tricia G. Bautista, Elisabeth Engeljakob, Mary Glaze Rosal

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Introduction: Residents are expected to convey unfavorable news, discuss prognoses, and relieve suffering, and address do-not-resuscitate orders, yet some report a lack of competence in providing this type of care. Recognizing this need, Family Medicine residency programs are incorporating end-of-life care from symptom and pain control, counseling, and humanistic qualities as core proficiencies in training. Objective: This study determined the competency of Family Medicine Residents from various institutions in Metro Manila on rendering care for the dying. Materials and Methods: Trainees completed a Palliative Care Evaluation tool to assess their degree of confidence in patient and family interactions, patient management, and attitudes towards hospice care. Results: Remarkably, only a small fraction of participants were confident in performing independent management of terminal delirium and dyspnea. Fewer than 30% of residents can do the following without supervision: discuss medication effects and patient wishes after death, coping with pain, vomiting and constipation, and reacting to limited patient decision-making capacity. Half of the respondents had confidence in supporting the patient or family member when they become upset. Majority expressed confidence in many end-of-life care skills if supervision, coaching and consultation will be provided. Most trainees believed that pain medication should be given as needed to terminally ill patients. There was also uncertainty as to the most appropriate person to make end-of-life decisions. These attitudes may be influenced by personal beliefs rooted in cultural upbringing as well as by personal experiences with death in the family, which may also affect their participation and confidence in caring for the dying. Conclusion: Enhancing the quality and quantity of end-of-life care experiences during residency with sufficient supervision and role modeling may lead to knowledge and skill improvement to ensure quality of care. Fostering bedside learning opportunities during residency is an appropriate venue for teaching interventions in end-of-life care education.

Keywords: end of life care, geriatrics, palliative care, residency training skill

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Authors: Cibele F. Oliveira, Debora P. Jaeschke, Rodrigo R. Laurino, Amanda R. Andrade, Ligia D. F. Marczak

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Raspberry is well-known as a good source of phenolic compounds, mainly anthocyanin. Some studies pointed out the importance of these bioactive compounds consumption, which is related to the decrease of the risk of cancer and cardiovascular diseases. The most consumed raspberry products are juices, yogurts, ice creams and jellies and, to ensure the safety of these products, raspberry is commonly pasteurized, for enzyme and microorganisms inactivation. Despite being efficient, the pasteurization process can lead to degradation reactions of the bioactive compounds, decreasing the products healthy benefits. Therefore, the aim of the present work was to evaluate moderate electric field (MEF) and ultrasound (US) technologies application on the pasteurization process of raspberry juice and compare the results with conventional pasteurization process. For this, phenolic compounds, anthocyanin content and physical-chemical parameters (pH, color changes, titratable acidity) of the juice were evaluated before and after the treatments. Moreover, microbiological analyses of aerobic mesophiles microorganisms, molds and yeast were performed in the samples before and after the treatments, to verify the potential of these technologies to inactivate microorganisms. All the pasteurization processes were performed in triplicate for 10 min, using a cylindrical Pyrex® vessel with a water jacket. The conventional pasteurization was performed at 90 °C using a hot water bath connected to the extraction cell. The US assisted pasteurization was performed using 423 and 508 W cm-2 (75 and 90 % of ultrasound intensity). It is important to mention that during US application the temperature was kept below 35 °C; for this, the water jacket of the extraction cell was connected to a water bath with cold water. MEF assisted pasteurization experiments were performed similarly to US experiments, using 25 and 50 V. Control experiments were performed at the maximum temperature of US and MEF experiments (35 °C) to evaluate only the effect of the aforementioned technologies on the pasteurization. The results showed that phenolic compounds concentration in the juice was not affected by US and MEF application. However, it was observed that the US assisted pasteurization, performed at the highest intensity, decreased anthocyanin content in 33 % (compared to in natura juice). This result was possibly due to the cavitation phenomena, which can lead to free radicals formation and accumulation on the medium; these radicals can react with anthocyanin decreasing the content of these antioxidant compounds in the juice. Physical-chemical parameters did not present statistical differences for samples before and after the treatments. Microbiological analyses results showed that all the pasteurization treatments decreased the microorganism content in two logarithmic cycles. However, as values were lower than 1000 CFU mL-1 it was not possible to verify the efficacy of each treatment. Thus, MEF and US were considered as potential alternative technologies for pasteurization process, once in the right conditions the application of the technologies decreased microorganism content in the juice and did not affected phenolic and anthocyanin content, as well as physical-chemical parameters. However, more studies are needed regarding the influence of MEF and US processes on microorganisms’ inactivation.

Keywords: MEF, microorganism inactivation, anthocyanin, phenolic compounds

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Authors: Sisaynew Tesfaw Admassu

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The strengthening of timber beams can be necessary for several reasons including the increase of live loads (possible in a historical building for a change of destination of use or upgrading to meet new requirements), the reduction of the resistant cross-sections following deterioration (attacks of biological agents such as fungi, and insects) or traumatic events (fires) and the excess of deflection in the members. The main purpose of strengthening an element is not merely to repair it, but also to prevent and minimize the appearance of future problems. This study did an experimental investigation on the behavior of reference and strengthened solid timber beams. The strengthening materials used in this study were CSM-450 glass fiber and steel materials for both flexural and shear strengthening techniques. Twenty-two solid timber beams of Juniperus procera (TID) species with the dimensions of 60 x 90 x 780 mm were used in the present study. The binding material to bond the strengthening materials with timber was general-purpose resin with Luperox® K10 MEKP catalyst. Three beams were used as control beams (unstrengthen beams) while the remaining nineteen beams were strengthened using the strengthening materials for flexure and shear. All the beams were tested for three points loading to failure by using a Universal Testing Machine, UTM-600kN machine. The experimental results showed that the strengthened beams performed better than the unstrengthen beams. The experimental result of flexural strengthened beams showed that the load-bearing capacity of strengthened beams increased between 16.34 – 42.55%. Four layers of Glass Fiber Reinforced polymer on the tension side of the beams was shown to be the most effective way to enhance load-bearing capacity. The strengthened beams also have an enhancement in their flexural stiffness. The stiffness of flexural strengthened beams was increased between 1.18 – 65.53% as compared to the control beams. The highest increment in stiffness has occurred on beams strengthened using 2x60 mm steel plates. The shear-strengthened beams showed a relatively small amount of performance as compared to flexural-strengthened beams; the reason is that the beams are sufficient for shear. The polyester resin used in the experimental work showed good performance in bonding agents between materials. The resin showed more effectiveness in GFRP materials than steel materials.

Keywords: heritage structures, strengthening, stiffness, adhesive, polyester resin, steel plates

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Authors: Dejen Alemu, Murray E. Jennex, Temtim Assefa

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Agriculture is the mainstay of the Ethiopian economy; however, the sector is dominated by smallholder farmers resulting in land fragmentation and suffering from low productivity. Due to these issues, much effort has been put into the transformation of the sector to bring about more sustainable rural economic development. Technological advancements have been applied for the betterment of farmers resulting in the design of tools that are potentially capable of supporting the agricultural sector; however, their use and relevance are still alien to the local rural communities. The notion of the creating, capturing and sharing of knowledge has also been repetitively raised by many international donor agencies to transform the sector, yet the most current approaches to knowledge dissemination focus on knowledge that originates from the western view of scientific rationality while overlooking the role of indigenous knowledge (IK). Therefore, in agricultural knowledge management system (KMS) development, the integration of IKS with scientific knowledge is a critical success factor. The present study aims to contribute in the discourse on how to best integrate scientific and IK in agricultural KMS development. The conceptual framework of the research is anchored in concepts drawn from the theory of situated learning in communities of practice (CoPs): knowledge brokering. Using the KMS development practices of Ethiopian agricultural transformation agency as a case area, this research employed an interpretive analysis using primary and secondary qualitative data acquired through in-depth semi-structured interviews and participatory observations. As a result, concepts are identified for understanding the integration of the two major knowledge systems (i.e., indigenous and scientific knowledge) and participation of relevant stakeholders in particular the local farmers in agricultural KMS development through the roles of extension agent as a knowledge broker including crossing boundaries, in-between position, translation and interpretation, negotiation, and networking. The research shall have a theoretical contribution in addressing the incorporation of a variety of knowledge systems in agriculture and practically to provide insight for policy makers in agriculture regarding the importance of IK integration in agricultural KMS development and support marginalized small-scale farmers.

Keywords: communities of practice, indigenous knowledge, knowledge management system development, knowledge brokering

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Authors: Pawel Magryta, Mateusz Paszko

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In today's world, a big problem of individual mobility, especially in large urban areas, occurs. Commonly used grand way of transport such as buses, trains or cars do not fulfill their tasks, i.e. they are not able to meet the increasing mobility needs of the growing urban population. Additional to that, the limitations of civil infrastructure construction in the cities exist. Nowadays the most common idea is to transfer the part of urban transport on the level of air transport. However to do this, there is a need to develop an individual flying transport vehicle. The biggest problem occurring in this concept is the type of the propulsion system from which the vehicle will obtain a lifting force. Standard propeller drives appear to be too noisy. One of the ideas is to provide the required take-off and flight power by the machine using the innovative ejector system. This kind of the system will be designed through a suitable choice of the three-dimensional geometric structure with special shape of nozzle in order to generate overpressure. The authors idea is to make a device that would allow to cumulate the overpressure using the a five-sided geometrical structure that will be limited on the one side by the blowing flow of air jet. In order to test this hypothesis a computer simulation study of aerodynamic drag of such 3D structures have been made. Based on the results of these studies, the tests on real model were also performed. The final stage of work was a comparative analysis of the results of simulation and real tests. The CFD simulation studies of air flow was conducted using the Star CD - Star Pro 3.2 software. The design of virtual model was made using the Catia v5 software. Apart from the objective to obtain advanced aviation propulsion system, all of the tests and modifications of 3D structures were also aimed at achieving high efficiency of this device while maintaining the ability to generate high value of overpressures. This was possible only in case of a large mass flow rate of air. All these aspects have been possible to verify using CFD methods for observing the flow of the working medium in the tested model. During the simulation tests, the distribution and size of pressure and velocity vectors were analyzed. Simulations were made with different boundary conditions (supply air pressure), but with a fixed external conditions (ambient temp., ambient pressure, etc.). The maximum value of obtained overpressure is 2 kPa. This value is too low to exploit the power of this device for the individual transport vehicle. Both the simulation model and real object shows a linear dependence of the overpressure values obtained from the different geometrical parameters of three-dimensional structures. Application of computational software greatly simplifies and streamlines the design and simulation capabilities. This work has been financed by the Polish Ministry of Science and Higher Education.

Keywords: aviation propulsion, CFD, 3d structure, aerodynamic drag

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Authors: M. Masroor Akhtar Khan, Moin Uddin, Lalit Varshney

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Recently, there has been a rapidly expanding interest in finding applications of natural polymers in view of value addition to agriculture. It is now being realized that radiation processing of natural polysaccharides can be beneficially utilized either to improve the existing methodologies used for processing the natural polymers or to impart value addition to agriculture by converting them into more useful form. Gamma-ray irradiation is employed to degrade and lower the molecular weight of some of the natural polysaccharides like alginates, chitosan and carrageenan into small sized oligomers. When these oligomers are applied to plants as foliar sprays, they elicit various kinds of biological and physiological activities, including promotion of plant growth, seed germination, shoot elongation, root growth, flower production, suppression of heavy metal stress, etc. Furthermore, application of these oligomers can shorten the harvesting period of various crops and help in reducing the use of insecticides and chemical fertilizers. In recent years, the oligomers of sodium alginate obtained by irradiating the latter with gamma-rays at 520 kGy dose are being employed. It was noticed that the oligomers derived from the natural polysaccharides could induce growth, photosynthetic efficiency, enzyme activities and most importantly the production of secondary metabolite in the plants like Artemisia annua, Beta vulgaris, Catharanthus roseus, Chrysopogon zizanioides, Cymbopogon flexuosus, Eucalyptus citriodora, Foeniculum vulgare, Geranium sp., Mentha arvensis, Mentha citrata, Mentha piperita, Mentha virdis, Papaver somniferum and Trigonella foenum-graecum. As a result of the application of these oligomers, the yield and/or contents of the active constituents of the aforesaid plants were significantly enhanced. The productivity, as well as quality of medicinal and aromatic plants, may be ameliorated by this novel technique in an economical way as a very little quantity of these irradiated (depolymerised) polysaccharides is needed. Further, this is a very safe technique, as we did not expose the plants directly to radiation. The radiation was used to depolymerize the polysaccharides into oligomers.

Keywords: essential oil, medicinal and aromatic plants, plant production, radiation processed polysaccharides, active constituents

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Authors: Savannah Rugg, Carlo Moreno, Pushpa Soti, Alexis Racelis

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Situated in deep South Texas, the Lower Rio Grande Valley (LRGV) is considered one the most productive agricultural regions in the southern US. With the highest concentration of organic farms in the state (Hidalgo county), the LRGV has a strong potential to be leaders in sustainable agriculture. Finding management practices that comply with organic certification and increase the health of the agroecosytem and the farmers working the land is increasingly pertinent. Cover cropping, or the intentional planting of non-cash crop vegetation, can serve multiple functions in an agroecosystem by decreasing environmental pollutants that originate from the agroecosystem, reducing inputs needed for crop production, and potentially decreasing on-farm costs for farmers—overall increasing the sustainability of the farm. Use of cover crops on otherwise fallow lands have shown to enhance ecosystem services such as: attracting native beneficial insects (pollinators), increase nutrient availability in topsoil, prevent nutrient leaching, increase soil organic matter, and reduces soil erosion. In this study, four cover crops (Lablab, Sudan Grass, Sunn Hemp, and Pearl Millet) were analyzed in the subtropical region of south Texas to see how their multiple functions enhance ecosystem services. The four cover crops were assessed to see their potential to harbor native insects, their potential to increase soil nitrogen, to increase soil organic matter, and to suppress weeds. The preliminary results suggest that these subtropical varieties of cover crops have potential to enhance ecosystem services on agricultural land in the RGV by increasing soil organic matter (in all varieties), increasing nitrogen in topsoil (Lablab, Sunn Hemp), and reducing weeds (Sudan Grass).

Keywords: cover crops, ecosystem services, subtropical agriculture, sustainable agriculture

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Authors: Moksha Singh

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The proponents of deinstitutionalization, including Goffman and others, in their works, have regarded institutions (orphanages to be specific) as regulated social arrangements that negatively impinge upon a resident’s development. They, therefore, propose alternative forms of care. However, even after five decades of this critique institutionalization remains the only hope for children with social, physical and mental disabilities in larger parts of the developing world such as the conflict affected state of Jammu and Kashmir in India. This paper is based on the experiences of children who lost their parents to insurgency and counter-insurgency operations and the rehabilitation process. This study is qualitative in nature and adopts descriptive-cum-exploratory research design. Using theoretical sampling, six orphanages and thirty one child residents who lost their parent(s) in the course of the armed conflict in the state of Jammu and Kashmir in India were studied in the year 2009-2010. It included interviews, observation, life histories and introspective accounts of the orphans and the management. The results were drawn through the qualitative examination, understanding, and interpretation of the primary and secondary data. The findings suggested that rehabilitation of these conflict-affected children is taking place mainly through residential child care facilities run by non-governmental bodies. Alternative forms of rehabilitation are not functional in the state because of various geopolitical and socio-cultural complexities. Even after five years of arriving at these conclusions and more, the state of Jammu and Kashmir still lacks a comprehensive rehabilitation plan for these children. This has further encouraged a mushroomed growth of legal and illegal institutions. Some of these institutions compromise the standard norms of functioning and yet remain the only hope for thousands rendered orphan. These institutions, therefore, are there to stay as other alternative forms of care are not available in the state. A comprehensive intervention policy is needed based on the cultural specifics of the state and incorporation of views of institutions offering aid, the state and the children. The paper introduces Small Group Residential Care Model through which it is expected that the restoration process can be made smooth and effective.

Keywords: armed conflict, children's rights, institutionalization, orphanages, rehabilitation

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Authors: W. Baumgartner, M. Welti, N. Hild, S. C. Hess, W. J. Stark, G. Meier Bürgisser, P. Giovanoli, J. Buschmann

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Perfusion bioreactors are used to solve problems in tissue engineering in terms of sufficient nutrient and oxygen supply. Such problems especially occur in critical size grafts because vascularization is often too slow after implantation ending up in necrotic cores. Biominerizable and biocompatible nanocomposite materials are attractive and suitable scaffold materials for bone tissue engineering because they offer mineral components in organic carriers – mimicking natural bone tissue. In addition, human adipose derived stem cells (ASCs) can potentially be used to increase bone healing as they are capable of differentiating towards osteoblasts or endothelial cells among others. In the present study, electrospun nanocomposite disks of poly-lactic-co-glycolic acid and amorphous calcium phosphate nanoparticles (PLGA/a-CaP) were seeded with human ASCs and eight disks were stacked in a bioreactor running with normal culture medium (no differentiation supplements). Under continuous perfusion and uniaxial cyclic compression, load-displacement curves as a function of time were assessed. Stiffness and energy dissipation were recorded. Moreover, stem cell densities in the layers of the piled scaffold were determined as well as their morphologies and differentiation status (endothelial cell differentiation, chondrogenesis and osteogenesis). While the stiffness of the cell free constructs increased over time caused by the transformation of the a-CaP nanoparticles into flake-like apatite, ASC-seeded constructs showed a constant stiffness. Stem cell density gradients were histologically determined with a linear increase in the flow direction from the bottom to the top of the 3.5 mm high pile (r2 > 0.95). Cell morphology was influenced by the flow rate, with stem cells getting more roundish at higher flow rates. Less than 1 % osteogenesis was found upon osteopontin immunostaining at the end of the experiment (9 days), while no endothelial cell differentiation and no chondrogenesis was triggered under these conditions. All ASCs had mainly remained in their original pluripotent status within this time frame. In summary, we have fabricated a critical size bone graft based on a biominerizable bone-biomimetic nanocomposite with preserved stiffness when seeded with human ASCs. The special feature of this bone graft was that ASC densities inside the piled construct varied with a linear gradient, which is a good starting point for tissue engineering interfaces such as bone-cartilage where the bone tissue is cell rich while the cartilage exhibits low cell densities. As such, this tissue-engineered graft may act as a bone-cartilage interface after the corresponding differentiation of the ASCs.

Keywords: bioreactor, bone, cartilage, nanocomposite, stem cell gradient

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Authors: Alan T. Sassler

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Biofouling is a significant issue for ships, especially those based in warm water ports. Biofouling damages hull coatings, degrades platform hydrodynamics, blocks cooling water intakes, and returns, reduces platform range and speed, and increases fuel consumption. Although platforms are protected to some degree by antifouling paints, these paints are much less effective on stationary platforms, and problematic biofouling can occur on antifouling paint-protected stationary platforms in some environments in as little as a matter of weeks. Remediation hull cleaning operations are possible, but they are very expensive, sometimes result in damage to the vessel’s paint or hull and are generally not completely effective. Ultrasound with sufficient intensity focused on specific frequency ranges can be used to prevent the growth of biofouling organisms. The use of ultrasound to prevent biofouling isn't new, but systems to date have focused on protecting platforms by shaking the hull using internally mounted transducers similar to those used in ultrasonic cleaning machines. While potentially effective, this methodology doesn't scale well to large platforms, and there are significant costs associated with installing and maintaining these systems, which dwarf the initial purchase price. An alternative approach has been developed, which uses highly directional pier-mounted transducers to project high-intensity spread-spectrum ultrasonic energy into the water column focused near the surface. This focused energy has been shown to prevent biofouling at ranges of up to 50 meters from the source. Spreading the energy out over a multi-kilohertz band makes the system both more effective and more environmentally friendly. This system has been shown to be both effective and inexpensive in small-scale testing and is now being characterized on a larger scale in selected marinas. To date, test results have been collected in Florida marinas suggesting that this approach can be used to keep ensonified areas of thousands of square meters free from biofouling, although care must be taken to minimize shaded areas.

Keywords: biofouling, ultrasonic, environmentally friendly antifoulant, marine protection, antifouling

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Authors: Huanru Wang, Jianzhun Jiang

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At present, the preparation of the catalyst by carbon carrier is one of the improvement directions of the C₂ pre-hydrogenation catalyst. Carbon materials can be prepared from coal direct liquefaction residues, coconut shells, biomass, etc., and the pore structure of carbon carrier materials can be adjusted through the preparation process; at high temperatures, the carbon carrier itself also shows certain catalytic activity. Therefore, this paper mainly selected typical activated carbon and coconut shell carbon as carbon carrier materials, studied their microstructure and surface properties, prepared a series of carbon-based catalysts loaded with Pd, and investigated the effects of the content of promoter Ag and the concentration of reductant on the structure and performance of the catalyst and its catalytic performance for the pre hydrogenation of C₂. In this paper, the carbon supports from two sources and the catalysts prepared by them were characterized in detail. The results showed that the morphology and structure of different supports and the performance of the catalysts prepared were also obviously different. The catalyst supported on coconut shell carbon has a small specific surface area and large pore diameter. The catalyst supported on activated carbon has a large specific surface area and rich pore structure. The active carbon support is mainly a mixture of amorphous graphite and microcrystalline graphite. For the catalyst prepared with coconut shell carbon as the carrier, the sample is very uneven, and its specific surface area and pore volume are irregular. Compared with coconut shell carbon, activated carbon is more suitable as the carrier of the C₂ hydrogenation catalyst. The conversion of acetylene, methyl acetylene, and butadiene decreased, and the ethylene selectivity increased after Ag was added to the supported Pd catalyst. When the amount of promoter Ag is 0.01-0.015%, the catalyst has relatively good catalytic performance. Ag and Pd form an alloying effect, thus reducing the effective demand for Ag. The Pd Ag ratio is the key factor affecting the catalytic performance. When the addition amount of Ag is 0.01-0.015%, the dispersion of Pd on the carbon support surface can be significantly improved, and the size of active particles can be reduced. The Pd Ag ratio is the main factor in improving the selectivity of the catalyst. When the additional amount of sodium formate is 1%, the catalyst prepared has both high acetylene conversion and high ethylene selectivity.

Keywords: C₂ hydrogenation, activated carbon, Ag promoter, Pd catalysts

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Authors: László L. Lippai

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In addition to the fact that mental health bears great significance to a particular individual, it can also be regarded as an organizational, community and societal resource. Within the Szeged Health Promotion Research Group, we conducted mental health surveys on two levels: The inhabitants of a medium-sized Hungarian town and students of a Hungarian university with a relatively big headcount were requested to participate in surveys whose goals were to define local government priorities and organization-level health promotion programmes, respectively. To facilitate professional decision-making, we defined three, pragmatically relevant, groups of the target population: the mentally healthy, the vulnerable and the endangered. In order to determine which group a person actually belongs to, we designed a simple and quick measurement tool, which could even be utilised as a smoothing method, the Mental State Questionnaire validity of the above three categories was verified by analysis of variance against psychological quality of life variables. We demonstrate the pragmatic significance of our method via the analyses of the scores of our two mental health surveys. On town level, during our representative survey in Hódmezővásárhely (N=1839), we found that 38.7% of the participants was mentally healthy, 35.3% was vulnerable, while 16.3% was considered as endangered. We were able to identify groups that were in a dramatic state in terms of mental health. For example, such a group consisted of men aged 45 to 64 with only primary education qualification and the ratios of the mentally healthy, vulnerable and endangered were 4.5, 45.5 and 50%, respectively. It was also astonishing to see to what a little extent qualification prevailed as a protective factor in the case of women. Based on our data, the female group aged 18 to 44 with primary education—of whom 20.3% was mentally healthy, 42.4% vulnerable and 37.3% was endangered—as well as the female group aged 45 to 64 with university or college degree—of whom 25% was mentally healthy, 51.3 vulnerable and 23.8% endangered—are to be handled as priority intervention target groups in a similarly difficult position. On organizational level, our survey involving the students of the University of Szeged, N=1565, provided data to prepare a strategy of mental health promotion for a university with a headcount exceeding 20,000. When developing an organizational strategy, it was important to gather information to estimate the proportions of target groups in which mental health promotion methods; for example, life management skills development, detection, psychological consultancy, psychotherapy, would be applied. Our scores show that 46.8% of the student participants were mentally healthy, 42.1% were vulnerable and 11.1% were endangered. These data convey relevant information as to the allocation of organizational resources within a university with a considerable headcount. In conclusion, The Mental State Questionnaire, as a valid smoothing method, is adequate to describe a community in a plain and informative way in the terms of mental health. The application of the method can promote the preparation, design and implementation of mental health promotion interventions. 

Keywords: health promotion, mental health promotion, mental state questionnaire, psychological well-being

Procedia PDF Downloads 276

Authors: A. Y. Purnama, N. Yasufuku

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The bridge structure is a building that has to be maintained, especially for the elastomeric bearing. The girder of the bridge needs to be lifted upward to maintain this elastomeric bearing, that needs high cost. Nowadays, integral abutment bridges are becoming popular. The integral abutment bridge is less costly because the elastomeric bearings are eliminated, which reduces the construction cost and maintenance costs. However, when this elastomeric bearing removed, the girder movement due to environmental thermal forces directly support by pile foundation, and it needs to be considered in the design. In case of pile foundation in a stiff soil, in the top area of the pile cannot move freely due to the fixed condition by soil stiffness. Pre-bored pile system can be used to increase the flexibility of pile foundation using a pre-bored hole that filled with elastic materials, but the behavior of soil-pile interaction and soil response due to this system is still rarely explained. In this paper, an experimental study using small-scale laboratory model test conducted in a half size model. Single flexible pile model embedded in sandy soil with the pre-bored ring, which filled with the filler material. The testing box made from an acrylic glass panel as observation area of the pile shaft to monitor the displacement of the pile during the lateral loading. The failure behavior of the soil inside the pre-bored ring and around the pile shaft was investigated to determine the point of pile rotation and the movement of this point due to the pre-bored ring system along the pile shaft. Digital images were used to capture the deformations of the soil and pile foundation during the loading from the acrylic glass on the side of the testing box. The results were presented in the form of lateral load resistance charts against the pile shaft displacement. The failure pattern result also established due to the cyclic lateral loading. The movement of the rotational point was measured due to the pre-bored system filled with appropriate filler material. Based on the findings, design considerations for pre-bored pile system due to cyclic lateral loading can be introduced.

Keywords: failure behavior, pre-bored pile system, cyclic lateral loading, sandy soil

Procedia PDF Downloads 205

Authors: Vangmayee V. Subban, Suzan Deelan. Pinto, Somashekara Haralakatta Shivananjappa, Shwetha Prabhu, Jayashree S. Bhat

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Introduction and Need: During early years of schooling, the instruction in the schools mainly focus on children’s word decoding abilities. However, the skilled readers should master all the components of reading such as word decoding, reading fluency and comprehension. Nevertheless, the relationship between each component during the process of learning to read is less clear. The studies conducted in alphabetical languages have mixed opinion on relative contribution of word decoding and reading fluency on reading comprehension. However, the scenarios in alphasyllabary languages are unexplored. Aim and Objectives: The aim of the study was to explore the role of word decoding, reading fluency on reading comprehension abilities in children learning to read Kannada between the age ranges of 5.6 to 8.6 years. Method: In this cross sectional study, a total of 60 typically developing children, 20 each from Grade I, Grade II, Grade III maintaining equal gender ratio between the age range of 5.6 to 6.6 years, 6.7 to 7.6 years and 7.7 to 8.6 years respectively were selected from Kannada medium schools. The reading fluency and reading comprehension abilities of the children were assessed using Grade level passages selected from the Kannada text book of children core curriculum. All the passages consist of five questions to assess reading comprehension. The pseudoword decoding skills were assessed using 40 pseudowords with varying syllable length and their Akshara composition. Pseudowords are formed by interchanging the syllables within the meaningful word while maintaining the phonotactic constraints of Kannada language. The assessment material was subjected to content validation and reliability measures before collecting the data on the study samples. The data were collected individually, and reading fluency was assessed for words correctly read per minute. Pseudoword decoding was scored for the accuracy of reading. Results: The descriptive statistics indicated that the mean pseudoword reading, reading comprehension, words accurately read per minute increased with the Grades. The performance of Grade III children found to be higher, Grade I lower and Grade II remained intermediate of Grade III and Grade I. The trend indicated that reading skills gradually improve with the Grades. Pearson’s correlation co-efficient showed moderate and highly significant (p=0.00) positive co-relation between the variables, indicating the interdependency of all the three components required for reading. The hierarchical regression analysis revealed 37% variance in reading comprehension was explained by pseudoword decoding and was highly significant. Subsequent entry of reading fluency measure, there was no significant change in R-square and was only change 3%. Therefore, pseudoword-decoding evolved as a single most significant predictor of reading comprehension during early Grades of reading acquisition. Conclusion: The present study concludes that the pseudoword decoding skills contribute significantly to reading comprehension than reading fluency during initial years of schooling in children learning to read Kannada language.

Keywords: alphasyllabary, pseudo-word decoding, reading comprehension, reading fluency

Procedia PDF Downloads 229

Authors: Ola Jon Mork, Lars Andre Giske, Emil Bjørlykhaug

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Stabilization of critical processes in order to have the right quality of the products, more efficient production and smoother flow is a key issue in lean production. This paper presents how simulation of key welding processes can stabilize complicated welding processes in small scale production, and how simulation can impact the entire production concept seen from the perspective of lean production. First, a field study was made to learn the production processes in the factory, and subsequently the field study was transformed into a value stream map to get insight into each operation, the quality issues, operation times, lead times and flow of materials. Valuable practical knowledge of how the welding operations were done by operators, appropriate tools and jigs, and type of robots that could be used, was collected. All available information was then implemented into a simulation environment for further elaboration and development. Three researchers, the management of the company and skilled operators at the work floor where working on the project over a period of eight months, and a detailed description of the process was made by the researchers. The simulation showed that simulation could solve a number of technical challenges, the robot program can be tuned in off line mode, and the design and testing of the robot cell could be made in the simulator. Further on the design of the product could be optimized for robot welding and the jigs could be designed and tested in simulation environment. This means that a key issue of lean production can be solved; the welding operation will work with almost 100% performance when it is put into real production. Stabilizing of one key process is critical to gain control of the entire value chain, then a Takt Time can be established and the focus can be directed towards the next process in the production which should be stabilized. Results show that industrial parameters like welding time, welding cost and welding quality can be defined on the simulation stage. Further on, this gives valuable information for calculation of the factories business performance, like manufacturing volume and manufacturing efficiency. Industrial impact from simulation is more efficient implementation of lean manufacturing, since the welding process can be stabilized. More research should be done to gain more knowledge about simulation as a tool for implementation of lean, especially where there complex processes.

Keywords: simulation, lean, stabilization, welding process

Procedia PDF Downloads 296

Authors: D. H. Tejavathi

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Medicinal plants are globally valuable sources of herbal products. Wild populations of many medicinal plants are facing threat of extinction because of their narrow distribution, endemicity, and degradation of specific habitats. Micropropagation is an established in vitro technique by which large number of clones can be obtained from a small bit of explants in a short span of time within a limited space. Mycorrhization can minimize the transient transplantation shock, experienced by the micropropagated plants when they are transferred from lab to land. AM fungal association improves the physiological status of the host plants through better uptake of water and nutrients, particularly phosphorus. Consequently, the growth performance and biosynthesis of active principles are significantly enhanced in AM fungal treated plants. Bacopa monnieri, Andrographis paniculata, Agave vera-curz, Drymaria cordata and Majorana hortensis, important medicinal plants used in various indigenous systems of medicines, are selected for the present study. They form the main constituents of many herbal formulations. Standard in vitro techniques were followed to obtain the micropropagated plants. Shoot tips and nodal segments were used as explants. Explants were cultured on Murashige and Skoog, and Phillips and Collins media supplemented with various combinations of growth regulators. Multiple shoots were obtained on a media containing both auxins and cytokinins at various concentrations and combinations. Multiple shoots were then transferred to rooting media containing auxins for root induction. Thus, obtained in vitro regenerated plants were subjected to brief acclimatization before transferring them to land. One-month-old in vitro plants were treated with AM fungi, and the symbiotic effect on the overall growth parameters was analyzed. It was found that micropropagation coupled with mycorrhization has significant effect on the enhancement of biomass and biosynthesis of active principles in these selected medicinal plants. In vitro techniques coupled with mycorrhization have opened a possibility of obtaining better clones in respect of enhancement of biomass and biosynthesis of active principles. Beneficial effects of AM fungal association with medicinal plants are discussed.

Keywords: cultivation, medicinal plants, micropropagation, mycorrhization

Procedia PDF Downloads 145

Authors: Hakimullah Hakim, Chiharu Toyofuku, Mari Ota, Mayuko Suzuki, Miyuki Komura, Masashi Yamada, Md. Shahin Alam, Natthanan Sangsriratanakul, Dany Shoham, Kazuaki Takehara

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Disinfectants and their application are essential part of infection control strategies and enhancement of biosecurity at farms, worldwide. Alkaline agents are well known for their strong and long term antimicrobial capacities and most frequently are applied at farms for control and prevention of biological hazards. However, inadequate information regarding such materials’ capacities to inactivate pathogens and their improper applications fail farmers to achieve the mentioned goal. Thus, this requires attention to further evaluate their efficacies, under different conditions and in different ways. Here in this study we evaluated bactericidal efficacies of food additive grade of calcium hydroxide (FdCa(OH)2) powder derived from natural calcium carbonates obtained from limestone (Fine Co., Ltd., Tokyo, Japan), and bioceramic powder (BCX) derived from chicken feces at pH 13 (NMG environmental development Co., Ltd., Tokyo, Japan), for their efficacies to inactivate bacteria in feces. [Materials & Methods] Chicken feces were inoculated by 100 µl Escherichia coli and Salmonella Infantis in falcon tubes, individually, then FdCa(OH)2 or BCX powders were individually added to make final concentration of 0, 5, 10, 20 and 30% (w/w) in total weight of 0.5g, followed by properly mixing and incubating at room temperature for certain periods of time, in a dark place. Afterwards, 10 ml 1M Tris-HCl (pH 7.2) was added onto them to reduce their pH, in order to stop powders’ activities and to harvest the remained viable bacteria, whereas using normal medium or dW2 to recover bacteria increases the mixture pH, and as a result bacteria would be inactivated soon; therefore, the latter practice brings about incorrect and misleading results. Samples were then inoculated on DHL agar plates in order to calculate colony forming units (CFU)/ml of viable bacteria. [Results and Discussion] FdCa(OH)2 powder at 10% and 5% required 3 hr and 6 hr exposure times, respectively, while BCX powder at 20% concentrations required 6 hr exposure time to kill the mentioned bacteria in feces down to lower than detectable level (≤ 3.6 log10 CFU/ml). This study confirmed capacities of FdCa(OH)2 and BCX powders to inactivate bacteria in feces, and both materials are environment friendly materials, with no risk to human or animal’s health. This finding helps farmers to properly apply alkaline agents in appropriate concentrations and exposure times in their farms, in order to prevent and control infectious diseases outbreaks and to enhance biosecurity. Finally, this finding may help farmers to implement better strategies for infections control in their livestock farms.

Keywords: bacterial inactivation, bioceramic, biosecurity at livestock farms, chicken feces

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Authors: Hendri Purwadi, Christine McCloud

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Triage is a complex decision-making process that aims to categorize a victim’s level of acuity and the need for medical assistance. Two common triage systems have been widely used in Mass Casualty Incidents (MCIs) and disaster situation are START (Simple triage algorithm and rapid treatment) and SALT (sort, asses, lifesaving, intervention, and treatment/transport). There is currently controversy regarding the effectiveness of SALT over START triage system. This systematic review aims to investigate and compare the effectiveness between SALT and START triage system in disaster and MCIs setting. Literatures were searched via systematic search strategy from 2009 until 2019 in PubMed, Cochrane Library, CINAHL, Scopus, Science direct, Medlib, ProQuest. This review included simulated-based and medical record -based studies investigating the accuracy and applicability of SALT and START triage systems of adult and children population during MCIs and disaster. All type of studies were included. Joana Briggs institute critical appraisal tools were used to assess the quality of reviewed studies. As a result, 1450 articles identified in the search, 10 articles were included. Four themes were identified by review, they were accuracy, under-triage, over-triage and time to triage per individual victim. The START triage system has a wide range and inconsistent level of accuracy compared to SALT triage system (44% to 94. 2% of START compared to 70% to 83% of SALT). The under-triage error of START triage system ranged from 2.73% to 20%, slightly lower than SALT triage system (7.6 to 23.3%). The over-triage error of START triage system was slightly greater than SALT triage system (START ranged from 2% to 53% compared to 2% to 22% of SALT). The time for applying START triage system was faster than SALT triage system (START was 70-72.18 seconds compared to 78 second of SALT). Consequently; The START triage system has lower level of under-triage error and faster than SALT triage system in classifying victims of MCIs and disaster whereas SALT triage system is known slightly more accurate and lower level of over-triage. However, the magnitude of these differences is relatively small, and therefore the effect on the patient outcomes is not significance. Hence, regardless of the triage error, either START or SALT triage system is equally effective to triage victims of disaster and MCIs.

Keywords: disaster, effectiveness, mass casualty incidents, START triage system, SALT triage system

Procedia PDF Downloads 107

Authors: Norihiro Kato, Yuriko Takayama

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Some gram-negative bacteria enable the simultaneous activation of gene expression involved in N-acylhomoserine lactone (AHL) dependent cell-to-cell communication system. Such regulatory system for the bacterial group behavior is termed as quorum sensing (QS) because a diffusible AHL signal can accumulate around the cell during the increase of the cell density and trigger activation of the sequential QS process. By blocking the QS, the expression of diverse genes related to infection, antibiotic production, and biofilm formation is inhibited. Conditioning of QS by regulation of the DNA-receptor-AHL interaction is a potential target for enhancing host defenses against pathogenicity. We focused on engineered application of transcriptional regulator SpnR produced in opportunistic human pathogen Serratia marcescens. The SpnR can interact with AHL signals at an N-terminal domain and also with a promoter region of a QS target gene at a C-terminal domain. As the initial process of the QS activation, the SpnR forms a complex with the AHL to enhance the expression of pig cluster; the SpnR normally acts as an activator for the expression of the QS-dependent gene. In this research, we attempt to artificially control QS by changing the role of SpnR. The QS-dependent prodigiosin production is expected to inhibit by externally added SpnR in the culture broth of AS-1 strain because the AHL concentration was kept below the threshold by AHL-SpnR complex formation. Maltose-binding protein (MBP)-tagged SpnR (MBP-SpnR) was overexpressed in Escherichia coli and purified using an affinity chromatography equipped with an amylose resin column. The specific interaction between AHL and MBP-SpnR was demonstrated by quartz crystal microbalance (QCM) sensor. AHL with amino end-group was coupled with COOH-terminated self-assembled monolayer prepared on a gold electrode of 27-MHz quartz crystal sensor using water-soluble carbodiimide. After the injection of MBP-SpnR into a cup-type sensor cell filled with the buffer solution, time course of resonant frequency change (ΔFs) was determined. A decrease of ΔFs clearly showed the uptake of MBP-SpnR onto the AHL-immobilized electrode. Furthermore, no binding affinity was observed after the heat-inactivation of MBP-SpnR at 80ºC. These results suggest that MBP-SpnR possesses a specific affinity for AHL. MBP-SpnR was added to the culture medium as an AHL trap to study inhibitory effects on intracellularly accumulated prodigiosin. With approximately 2 µM MBP-SpnR, the amount of prodigiosin induced was half that of the control without any additives. In conclusion, the function of SpnR could be switched by adding it to the cell culture. Exogenously added MBP-SpnR possesses high affinity for AHL derived from cells and acts as an inhibitor of AHL-mediated QS.

Keywords: intracellular signaling, microbial biotechnology, quorum sensing, transcriptional regulator

Procedia PDF Downloads 241

Authors: Silvia A. Magalhaes, Vasco P. De Freitas, Jose L. Alexandre

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Most of the European literature concerning energy efficiency and thermal comfort of dwellings assumes permanent heating and focuses on energy-saving measures. European National regulations are designed for those permanent comfort conditions. On the other hand, very few studies focus on the effect of the improvement measures in comfort reduction, for free-floating conditions or intermittent heating, in fuel poverty vulnerable countries. In Portugal, only 21% of the household energy consumptions (and 10% of the cost) are spent in space heating, while, on average European bills, this value rises to 67%. The mild climate, but mainly fuel poverty and cultural background, justifies these low heating practices. This study proposes a “passive discomfort” index definition, considering free-floating temperatures or with intermittent heating profiles (more realistic conditions), putting the focus on comfort rather than energy consumption (which is low for these countries). The aim is to compare both energy (regarding the legal framework of national regulation) and comfort (considering realistic conditions of use) to identify some correlation. It was developed an experimental campaign of indoor thermal conditions in a 19th building located in Porto with several apartments. One dwelling was chosen as a case study to carry out a sensitivity analysis. The results are discussed comparing both theoretical energy consumption (energy rates from national regulation) and discomfort (new index defined), for different insulation thicknesses, orientations, and intermittent heating profiles. The results show that the different passive options (walls insulation and glazing options) have a small impact on winter discomfort, which is always high for low heating profiles. Moreover, it was shown that the insulation thickness on walls has no influence, and the minimum insulation thickness considered is enough to achieve the same impact on discomfort reduction. Plus, for these low heating profiles, other conditions are critical, as the orientation. Finally, there isn’t an unequivocal relation between the energy label and the discomfort index. These and other results are surprising when compared with the most usual approaches, which assume permanent heating.

Keywords: dwellings in historical buildings, low-heating countries, mild climates, thermal comfort

Procedia PDF Downloads 94

Authors: Natalia Politaeva, Iuliia Smiatskaia, Iuliia Bazarnova, Iryna Atamaniuk, Kerstin Kuchta

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Nowadays, the progressive decrease of primary natural resources and ongoing upward trend in terms of energy demand, have resulted in development of new generation technological processes which are focused on step-wise production and residues utilization. Thus, microalgae-based 3^rd generation bioeconomy is considered one of the most promising approaches that allow production of value-added products and sophisticated utilization of residues biomass. In comparison to conventional biomass, microalgae can be cultivated in wide range of conditions without compromising food and feed production, and thus, addressing issues associated with negative social and environmental impacts. However, one of the most challenging tasks is to undergo seasonal variations and to achieve optimal growing conditions for indoor closed systems that can cover further demand for material and energetic utilization of microalgae. For instance, outdoor cultivation in St. Petersburg (Russia) is only suitable within rather narrow time frame (from mid-May to mid-September). At earlier and later periods, insufficient sunlight and heat for the growth of microalgae were detected. On the other hand, without additional physical effects, the biomass increment in summer is 3-5 times per week, depending on the solar radiation and the ambient temperature. In order to increase biomass production, scientists from all over the world have proposed various technical solutions for cultivators and have been studying the influence of various physical factors affecting biomass growth namely: magnetic field, radiation impact, and electric field, etc. In this paper, the influence of infrared radiation (IR) and fluorescent light on the growth rate of microalgae Chlorella sorokiniana has been studied. The cultivation of Chlorella sorokiniana was carried out in 500 ml cylindrical glass vessels, which were constantly aerated. To accelerate the cultivation process, the mixture was stirred for 15 minutes at 500 rpm following 120 minutes of rest time. At the same time, the metabolic needs in nutrients were provided by the addition of micro- and macro-nutrients in the microalgae growing medium. Lighting was provided by fluorescent lamps with the intensity of 2500 ± 300 lx. The influence of IR was determined using IR lamps with a voltage of 220 V, power of 250 W, in order to achieve the intensity of 13 600 ± 500 lx. The obtained results show that under the influence of fluorescent lamps along with the combined effect of active aeration and variable mixing, the biomass increment on the 2^nd day was three times, and on the 7^th day, it was eight-fold. The growth rate of microalgae under the influence of IR radiation was lower and has reached 22.6·10⁶ cells·mL^-1. However, application of IR lamps for the biomass growth allows maintaining the optimal temperature of microalgae suspension at approximately 25-28°C, which might especially be beneficial during the cold season in extreme climate zones.

Keywords: biomass, fluorescent lamp, infrared radiation, microalgae

Procedia PDF Downloads 157

Authors: Joanna Estkowska

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Sensory integration methods are very useful and improve daily functioning autistic and mentally disabled children. Autism is a neurobiological disorder that impairs one's ability to communicate with and relate to others as well as their sensory system. Children with autism, even highly functioning kids, can find it difficult to process language with surrounding noise or smells. They are hypersensitive to things we can ignore such as sight, sounds and touch. Adolescents with highly functioning autism or Asperger Syndrome can study Science and Math but the social aspect is difficult for them. Nature science is an area of study that attracts many of these kids. It is a systematic field in which the children can focus on a small aspect. If you follow these rules you can come up with an expected result. Sensory integration program and systematic classroom observation are quantitative methods of measuring classroom functioning and behaviors from direct observations. These methods specify both the events and behaviors that are to be observed and how they are to be recorded. Our students with and without autism attended the lessons in the classroom of nature science in the school and in the laboratory of University of Science and Technology in Bydgoszcz. The aim of this study is investigation the effects of sensory integration methods in teaching to students with autism. They were observed during experimental lessons in the classroom and in the laboratory. Their physical characteristics, sensory dysfunction, and behavior in class were taken into consideration by comparing their similarities and differences. In the chemistry classroom, every autistic student is paired with a mentor from their school. In the laboratory, the children are expected to wear goggles, gloves and a lab coat. The chemistry classes in the laboratory were held for four hours with a lunch break, and according to the assistants, the children were engaged the whole time. In classroom of nature science, the students are encouraged to use the interactive exhibition of chemical, physical and mathematical models constructed by the author of this paper. Our students with and without autism attended the lessons in those laboratories. The teacher's goals are: to assist the child in inhibiting and modulating sensory information and support the child in processing a response to sensory stimulation.

Keywords: autism spectrum disorder, science education, sensory integration techniques, student with special educational needs

Procedia PDF Downloads 171

Authors: P. Dhesi, R. Burns

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Background: The UK has one of the largest immigration detention estates in Europe and is under increasing scrutiny, particularly regarding the lack of transparency over the use of detention and the conditions. Therefore, this research seeks to explore the professional perceptions of the ability of immigration detention in the UK to promote health and dignity. Methods: A phenomenological approach to qualitative methods were used, with social constructivist theorisations of health and dignity. Seven semi-structured interviews were conducted using Microsoft Teams. Participants included a range of immigration detention stakeholders who have visited closed immigration detention centres in the UK in a professional capacity. Recorded interviews were transcribed verbatim, and analysis was data-driven through inductive reflexive thematic analysis of the entire data set to account for the small sample size. This study received ethical approval from University College London Research Ethics Committee. Results: Two global themes were created through analysis: apathetic place and hostile space. Apathetic place discusses the lack of concern for detainees' daily living and healthcare needs within immigration detention in the UK. This is explored through participants' perceptions of the lack of ability of monitoring and evaluation processes to ensure detainees are able to live with dignity and understand the unfulfilled duty of care that exists in detention. Hostile space discusses immigration detention in the UK as a wider system of hostility. This is explored through the disempowering impact on detainees, the perception of a failing system as a result of inadequate safeguarding procedures, and a belief that the intention of immigration detention is misaligned with its described purpose. Conclusion: This research explains why the current immigration detention system in the UK is unable to promote health and dignity, offering a social justice and action-orientated approach to research in this sphere. The findings strengthen the discourse against the use of detention as an immigration control tool in the UK. Implications for further research include a stronger emphasis on investigating alternatives to detention and culturally considerate opportunities for patient-centred healthcare.

Keywords: access to healthcare, dignity, health, immigration detention, migrant, refugee, UK

Procedia PDF Downloads 76

Authors: Irakli Gamkrelidze, David Shengelia, Tamara Tsutsunava, Giorgi Chichinadze, Giorgi Beridze, Ketevan Tedliashvili, Tamara Tsamalashvili

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The Loki crystalline massif crops out in the Caucasian region and the geological retrospective represent the northern marginal part of the Baiburt-Sevanian terrain (island arc), bordering with the Paleotethys oceanic basin in the north. The pre-Alpine basement of the massif is built up of Lower-Middle Paleozoic metamorphic complex (metasedimentary and metabasite rocks), Upper Devonian quartz-diorites and Late Variscan granites. Earlier metamorphic complex was considered as an indivisible set including suites with different degree of metamorphism. Systematic geologic, petrologic and geochemical investigations of the massif’s rocks suggest the different conception on composition, structure and formation conditions of the massif. In particular, there are two main rock types in the Loki massif: the oldest autochthonous series of gneissic quartz-diorites and cutting them granites. The massif is flanked on its western side by a volcano-sedimentary sequence, metamorphosed to low-T facies. Petrologic, metamorphic and structural differences in this sequence prove the existence of a number of discrete units (overthrust sheets). One of them, the metabasic sheet represents the fragment of ophiolite complex. It comprises transition types of the second and third layers of the Paleooceanic crust: the upper noncumulated part of the third layer gabbro component and the following lowest part of the parallel diabase dykes of the second layer. The ophiolites are represented by metagabbros, metagabbro-diabases, metadiabases and amphibolite schists. According to the content of petrogenic components and additive elements in metabasites is stated that the protolith of metabasites belongs to petrochemical type of tholeiitic series of basalts. The parental magma of metaophiolites is of E-MORB composition, and by petrochemical parameters, it is very close to the composition of intraplate basalts. The dykes of hypabissal leucocratic siliceous and medium magmatic rocks associated with the metaophiolite sheet form the separate complex. They are granitoids with the extremely low content of CaO and quartz-diorite porphyries. According to various petrochemical parameters, these rocks have mixed characteristics. Their formation took place in spreading conditions or in the areas of manifestation of plumes most likely of island arc type. The metamorphism degree of the metaophiolites corresponds to a very low stage of green schist facies. The rocks of the metaophiolite complex are obducted from the Paleotethys Ocean. Geological and paleomagnetic data show that the primary location of the ocean is supposed to be to the north of the Loki crystalline massif.

Keywords: the Caucasus, crystalline massif, ophiolites, tectonic sheet

Procedia PDF Downloads 254

Authors: Remo Waser, Simon Maranda, Anastasia Stamatiou, Ludger J. Fischer, Joerg Worlitschek

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In latent heat storage, a phase change material (PCM) is used to store thermal energy. The heat transfer rate during solidification is limited and considered as a key challenge in the development of latent heat storages. Thus, finned heat exchangers (HEX) are often utilized to increase the heat transfer rate of the storage system. In this study, a new modeling approach to calculating the heat transfer rate in latent thermal energy storages with complex HEX geometries is presented. This model allows for an optimization of the HEX design in terms of costs and thermal performance of the system. Modeling solidification processes requires the calculation of time-dependent heat conduction with moving boundaries. Commonly used computational fluid dynamic (CFD) methods enable the analysis of the heat transfer in complex HEX geometries. If applied to the entire storage, the drawback of this approach is the high computational effort due to small time steps and fine computational grids required for accurate solutions. An alternative to describe the process of solidification is the so-called temperature-based approach. In order to minimize the computational effort, a quasi-stationary assumption can be applied. This approach provides highly accurate predictions for tube heat exchangers. However, it shows unsatisfactory results for more complex geometries such as finned tube heat exchangers. The presented simulation model uses a temporal and spatial discretization of heat exchanger tube. The spatial discretization is based on the smallest possible symmetric segment of the HEX. The heat flow in each segment is calculated using finite volume method. Since the heat transfer fluid temperature can be derived using energy conservation equations, the boundary conditions at the inner tube wall is dynamically updated for each time step and segment. The model allows a prediction of the thermal performance of latent thermal energy storage systems using complex HEX geometries with considerably low computational effort.

Keywords: modelling of solidification, finned tube heat exchanger, latent thermal energy storage

Procedia PDF Downloads 240

Authors: Sima Aznavi, Poria Fajri, Hanif Livani

Abstract:

Smart homes are small energy systems which may be equipped with renewable energy sources, storage devices, and loads. Energy management strategy plays a main role in the efficient operation of smart homes. Effective energy scheduling of the renewable energy sources and storage devices guarantees efficient energy management in households while reducing the energy imports from the grid. Nevertheless, despite such strategies, independently day ahead energy schedules for multiple households can cause undesired effects such as high power exchange with the grid at certain times of the day. Therefore, the interactions between multiple smart home day ahead energy projections is a challenging issue in a smart grid system and if not managed appropriately, the imported energy from the power network can impose additional burden on the distribution grid. In this paper, a central energy management strategy for a network consisting of multiple households each equipped with renewable energy sources, storage devices, and Plug-in Electric Vehicles (PEV) is proposed. The decision-making strategy alongside the smart home energy management system, minimizes the energy purchase cost of the end users, while at the same time reducing the stress on the utility grid. In this approach, the smart home energy management system determines different operating scenarios based on the forecasted household daily load and the components connected to the household with the objective of minimizing the end user overall cost. Then, selected projections for each household that are within the same cost range are sent to the central decision-making system. The central controller then organizes the schedules to reduce the overall peak to average ratio of the total imported energy from the grid. To validate this approach simulations are carried out for a network of five smart homes with different load requirements and the results confirm that by applying the proposed central energy management strategy, the overall power demand from the grid can be significantly flattened. This is an effective approach to alleviate the stress on the network by distributing its energy to a network of multiple households over a 24- hour period.

Keywords: energy management, renewable energy sources, smart grid, smart home

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