Search results for: high performance concrete

Authors: Ali H. Daraji, Jack M. Hale, Ye Jianqiao

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With the extensive use of high specific strength structures to optimise the loading capacity and material cost in aerospace and most engineering applications, much effort has been expended to develop intelligent structures for active vibration reduction and structural health monitoring. These structures are highly flexible, inherently low internal damping and associated with large vibration and long decay time. The modification of such structures by adding lightweight piezoelectric sensors and actuators at efficient locations integrated with an optimal control scheme is considered an effective solution for structural vibration monitoring and controlling. The size and location of sensor and actuator are important research topics to investigate their effects on the level of vibration detection and reduction and the amount of energy provided by a controller. Several methodologies have been presented to determine the optimal location of a limited number of sensors and actuators for small-scale structures. However, these studies have tackled this problem directly, measuring the fitness function based on eigenvalues and eigenvectors achieved with numerous combinations of sensor/actuator pair locations and converging on an optimal set using heuristic optimisation techniques such as the genetic algorithms. This is computationally expensive for small- and large-scale structures subject to optimise a number of s/a pairs to suppress multiple vibration modes. This paper proposes an efficient method to determine optimal locations for a limited number of sensor/actuator pairs for active vibration reduction of a flexible structure based on finite element method and Hamilton’s principle. The current work takes the simplified approach of modelling a structure with sensors at all locations, subjecting it to an external force to excite the various modes of interest and noting the locations of sensors giving the largest average percentage sensors effectiveness measured by dividing all sensor output voltage over the maximum for each mode. The methodology was implemented for a cantilever plate under external force excitation to find the optimal distribution of six sensor/actuator pairs to suppress the first six modes of vibration. It is shown that the results of the optimal sensor locations give good agreement with published optimal locations, but with very much reduced computational effort and higher effectiveness. Furthermore, it is shown that collocated sensor/actuator pairs placed in these locations give very effective active vibration reduction using optimal linear quadratic control scheme.

Keywords: optimisation, plate, sensor effectiveness, vibration control

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Authors: Mehran Nozari-Asbemarz, Italo Pisano, Simin Arshi, Edmond Magner, James J. Leahy

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Integrating electrolytic synthesis with renewable energy makes it feasible to address urgent environmental and energy challenges. Conventional water electrolyzers concurrently produce H₂ and O₂, demanding additional procedures in gas separation to prevent contamination of H₂ with O₂. Moreover, the oxygen evolution reaction (OER), which is sluggish and has a low overall energy conversion efficiency, does not deliver a significant value product on the electrode surface. Compared to conventional water electrolysis, integrating electrolytic hydrogen generation from water with thermodynamically more advantageous aqueous organic oxidation processes can increase energy conversion efficiency and create value-added compounds instead of oxygen at the anode. One strategy is to use renewable and sustainable carbon sources from biomass, which has a large annual production capacity and presents a significant opportunity to supplement carbon sourced from fossil fuels. Numerous catalytic techniques have been researched in order to utilize biomass economically. Because of its safe operating conditions, excellent energy efficiency, and reasonable control over production rate and selectivity using electrochemical parameters, electrocatalytic upgrading stands out as an appealing choice among the numerous biomass refinery technologies. Therefore, we propose a broad framework for coupling H2 generation from water splitting with oxidative biomass upgrading processes. Four representative biomass targets were considered for oxidative upgrading that used a hierarchically porous CoFe-MOF/LDH @ Graphite Paper bifunctional electrocatalyst, including glucose, ethanol, benzyl, furfural, and 5-hydroxymethylfurfural (HMF). The potential required to support 50 mA cm-2 is considerably lower than (~ 380 mV) the potential for OER. All four compounds can be oxidized to yield liquid byproducts with economic benefit. The electrocatalytic oxidation of glucose to the value-added products, gluconic acid, glucuronic acid, and glucaric acid, was examined in detail. The cell potential for combined H₂ production and glucose oxidation was substantially lower than for water splitting (1.44 V(RHE) vs. 1.82 V(RHE) for 50 mA cm-2). In contrast, the oxidation byproduct at the anode was significantly more valuable than O₂, taking advantage of the more favorable glucose oxidation in comparison to the OER. Overall, such a combination of HER and oxidative biomass valorization using electrocatalysts prevents the production of potentially explosive H₂/O₂mixtures and produces high-value products at both electrodes with lower voltage input, thereby increasing the efficiency and activity of electrocatalytic conversion.

Keywords: biomass, electrocatalytic, glucose oxidation, hydrogen evolution

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Authors: Jurriaan Gillissen

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This work is concerned with stabilizing the numerical integration of the Navier-Stokes equation (NSE), backwards in time. Applications involve the detection of sources of, e.g., sound, heat, and pollutants. Stable reverse numerical integration of parabolic differential equations is also relevant for image de-blurring. While the literature addresses the reverse integration problem of the advection-diffusion equation, the problem of numerical reverse integration of the NSE has, to our knowledge, not yet been addressed. Owing to the presence of viscosity, the NSE is irreversible, i.e., when going backwards in time, the fluid behaves, as if it had a negative viscosity. As an effect, perturbations from the perfect solution, due to round off errors or discretization errors, grow exponentially in time, and reverse integration of the NSE is inherently unstable, regardless of using an implicit time integration scheme. Consequently, some sort of filtering is required, in order to achieve a stable, numerical, reversed integration. The challenge is to find a filter with a minimal adverse affect on the accuracy of the reversed integration. In the present work, we explore an adjoint gradient method (AGM) to achieve this goal, and we apply this technique to two-dimensional (2D), decaying turbulence. The AGM solves for the initial velocity field u0 at t = 0, that, when integrated forward in time, produces a final velocity field u1 at t = 1, that is as close as is feasibly possible to some specified target field v1. The initial field u0 defines a minimum of a cost-functional J, that measures the distance between u1 and v1. In the minimization procedure, the u0 is updated iteratively along the gradient of J w.r.t. u0, where the gradient is obtained by transporting J backwards in time from t = 1 to t = 0, using the adjoint NSE. The AGM thus effectively replaces the backward integration by multiple forward and backward adjoint integrations. Since the viscosity is negative in the adjoint NSE, each step of the AGM is numerically stable. Nevertheless, when applied to turbulence, the AGM develops instabilities, which limit the backward integration to small times. This is due to the exponential divergence of phase space trajectories in turbulent flow, which produces a multitude of local minima in J, when the integration time is large. As an effect, the AGM may select unphysical, noisy initial conditions. In order to improve this situation, we propose two remedies. First, we replace the integration by a sequence of smaller integrations, i.e., we divide the integration time into segments, where in each segment the target field v1 is taken as the initial field u0 from the previous segment. Second, we add an additional term (regularizer) to J, which is proportional to a high-order Laplacian of u0, and which dampens the gradients of u0. We show that suitable values for the segment size and for the regularizer, allow a stable reverse integration of 2D decaying turbulence, with accurate results for more then O(10) turbulent, integral time scales.

Keywords: time reversed integration, parabolic differential equations, adjoint gradient method, two dimensional turbulence

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Authors: Abeer Al Kalbani

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Oman is a sub-tropical country with limited water resources, harsh weather and limited soil fertility, constraining food production. Therefore, it largely depends on international markets to assure supply of food. In the light of these circumstances, food security in Oman is defined as the ability of the country to grant the staple food needs of people (e.g. rice, wheat, lentil, sugar, dates, dairy products, fish and plant or vegetable oils). It also involves exporting local goods with high production rates to exchange them with required food products. This concept of food security includes the availability of food through production and/or importing, stability of the market prices during all circumstances, and the ability of people to meet their needs within their income capabilities. As a result, most of the food security work is focused on availability and access dimensions of the issue. Not much research is focused on the utilization aspect of food security in Oman. Although women play a vital role in food security, there is limited research on women’s role in food security neither in Oman nor in neighboring Gulf countries. Women play an important role not only by carrying the responsibility of feeding their families but also by setting the consumption model for the household. Therefore, the research aims to contribute to the work done on food security in Oman and similar regions of the world by studying the role women play at the utilization level. Methods used in this research include Qualitative unstructured interviews, focus groups, survey questionnaire and an experimental study. Based on the FAO definition of food security, it consists of availability, access, utilization and sustainability. Results from a pilot study conducted for this research on two groups of women in Oman; urban and rural women, showed that women in Oman are responsible for achieving these four pillars at the household level. Moreover, awareness of women increased as their educational level increased. Urban women showed more awareness and openness to adopt healthier and proper food related choices than rural women. Urban women seem also more open than rural women to new ideas and concepts and ways to healthier food. However, both urban and rural women claim that no training and educational programs are available for them and awareness of food security in general remains relatively low in both groups. In the light of these findings, this research attempts to further investigate the social beliefs, practices and attitudes women adopt in relation to food purchase, storage, preparation and consumption as considered as important parts of the food system. It also seeks to examine the effect of educational training programs and media on the level of women awareness on the issue.

Keywords: food security, household food security, utilization, role of women

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Authors: Tomas Makaras, Gintaras Svecevičius

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Landfill waste is a common problem as it has an economic and environmental impact even if it is closed. Landfill waste contains a high density of various persistent compounds such as heavy metals, organic and inorganic materials. As persistent compounds are slowly-degradable or even non-degradable in the environment, they often produce sublethal or even lethal effects on aquatic organisms. The aims of the present study were to estimate sublethal effects of the Kairiai landfill (WGS: 55°55‘46.74“, 23°23‘28.4“) leachate on the locomotor activity of rainbow trout Oncorhynchus mykiss juveniles using the original system package developed in our laboratory for automated monitoring, recording and analysis of aquatic organisms’ activity, and to determine patterns of fish behavioral response to sublethal effects of leachate. Four different concentrations of leachate were chosen: 0.125; 0.25; 0.5 and 1.0 mL/L (0.0025; 0.005; 0.01 and 0.002 as part of 96-hour LC50, respectively). Locomotor activity was measured after 5, 10 and 30 minutes of exposure during 1-minute test-periods of each fish (7 fish per treatment). The threshold-effect-concentration amounted to 0.18 mL/L (0.0036 parts of 96-hour LC50). This concentration was found to be even 2.8-fold lower than the concentration generally assumed to be “safe” for fish. At higher concentrations, the landfill leachate solution elicited behavioral response of test fish to sublethal levels of pollutants. The ability of the rainbow trout to detect and avoid contaminants occurred after 5 minutes of exposure. The intensity of locomotor activity reached a peak within 10 minutes, evidently decreasing after 30 minutes. This could be explained by the physiological and biochemical adaptation of fish to altered environmental conditions. It has been established that the locomotor activity of juvenile trout depends on leachate concentration and exposure duration. Modeling of these parameters showed that the activity of juveniles increased at higher leachate concentrations, but slightly decreased with the increasing exposure duration. Experiment results confirm that the behavior of rainbow trout juveniles is a sensitive and rapid biomarker that can be used in combination with the system for fish behavior monitoring, registration and analysis to determine sublethal concentrations of pollutants in ambient water. Further research should be focused on software improvement aimed to include more parameters of aquatic organisms’ behavior and to investigate the most rapid and appropriate behavioral responses in different species. In practice, this study could be the basis for the development and creation of biological early-warning systems (BEWS).

Keywords: fish behavior biomarker, landfill leachate, locomotor activity, rainbow trout juveniles, sublethal effects

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Authors: Jayme R. T. Silva, Paulo G. P. Toro, Angelo Passaro, Giannino P. Camillo, Antonio C. Oliveira

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An in-house C++ code has been developed, at the Prof. Henry T. Nagamatsu Laboratory of Aerothermodynamics and Hypersonics from the Institute of Advanced Studies (Brazil), to estimate the aerothermodynamic properties around the Hypersonic Vehicle Integrated to the Scramjet. In the future, this code will be applied to the design of the Brazilian Scramjet Technological Demonstrator 14-X B. The first step towards accomplishing this objective, is to apply the in-house C++ code at the leading edge of a flat plate, simulating the leading edge of the 14-X Hypersonic Vehicle, making possible the wave phenomena of oblique shock and boundary layer to be analyzed. The development of modern hypersonic space vehicles requires knowledge regarding the characteristics of hypersonic flows in the vicinity of a leading edge of lifting surfaces. The strong interaction between a shock wave and a boundary layer, in a high supersonic Mach number 4 viscous flow, close to the leading edge of the plate, considering no slip condition, is numerically investigated. The small slip region is neglecting. The study consists of solving the fluid flow equations for unstructured meshes applying the SIMPLE algorithm for Finite Volume Method. Unstructured meshes are generated by the in-house software ‘Modeler’ that was developed at Virtual’s Engineering Laboratory from the Institute of Advanced Studies, initially developed for Finite Element problems and, in this work, adapted to the resolution of the Navier-Stokes equations based on the SIMPLE pressure-correction scheme for all-speed flows, Finite Volume Method based. The in-house C++ code is based on the two-dimensional Navier-Stokes equations considering non-steady flow, with nobody forces, no volumetric heating, and no mass diffusion. Air is considered as calorically perfect gas, with constant Prandtl number and Sutherland's law for the viscosity. Solutions of the flat plate problem for Mach number 4 include pressure, temperature, density and velocity profiles as well as 2-D contours. Also, the boundary layer thickness, boundary conditions, and mesh configurations are presented. The same problem has been solved by the academic license of the software Ansys Fluent and for another C++ in-house code, which solves the fluid flow equations in structured meshes, applying the MacCormack method for Finite Difference Method, and the results will be compared.

Keywords: boundary-layer, scramjet, simple algorithm, shock wave

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Authors: Gómez S. Jennifer, Méndez V. Camila, Moncayo M. Diana, Vega M. Lizeth

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The cape gooseberry is a climacteric fruit; Colombia is one of the principal exporters in the world. The environmental condition of temperature and relative moisture decreases the titratable acidity and pH. These conditions and fruit maturation result in the fungal proliferation of Botrytis cinerea disease. Plastic packaging for fresh cape gooseberries was used for mechanical damage protection but created a suitable atmosphere for fungal growth. Beta-cyclodextrins are currently implemented as coatings for the encapsulation of hydrophobic compounds, for example, with bioactive compounds from essential oils such as cinnamaldehyde, which has a high antimicrobial capacity. However, it is a volatile substance. In this article, the casting method was used to obtain a polylactic acid (PLA) polymer film containing the beta-cyclodextrin-cinnamaldehyde inclusion complex, generating an insert that allowed the controlled release of the antifungal substance in packed cape gooseberries to decrease contamination by Botrytis cinerea in a latent state during storage. For the encapsulation technique, three ratios for the cinnamaldehyde: beta-cyclodextrin inclusion complex were proposed: (25:75), (40:60), and (50:50). Spectrophotometry, colorimetry in L*a*b* coordinate space and scanning electron microscopy (SEM) were made for the complex characterization. Subsequently, two ratios of tween and water (40:60) and (50:50) were used to obtain the polylactic acid (PLA) film. To determine mechanical and physical parameters of colourimetry in L*a*b* coordinate space, atomic force microscopy and stereoscopy were done to determine the transparency and flexibility of the film; for both cases, Statgraphics software was used to determine the best ratio in each of the proposed phases, where for encapsulation it was (50:50) with an encapsulation efficiency of 65,92%, and for casting the ratio (40:60) obtained greater transparency and flexibility that permitted its incorporation into the polymeric packaging. A liberation assay was also developed under ambient temperature conditions to evaluate the concentration of cinnamaldehyde inside the packaging through gas chromatography for three weeks. It was found that the insert had a controlled release. Nevertheless, a higher cinnamaldehyde concentration is needed to obtain the minimum inhibitory concentration for the fungus Botrytis cinerea (0.2g/L). The homogeneity of the cinnamaldehyde gas phase inside the packaging can be improved by considering other insert configurations. This development aims to impact emerging food preservation technologies with the controlled release of antifungals to reduce the affectation of the physico-chemical and sensory properties of the fruit as a result of contamination by microorganisms in the postharvest stage.

Keywords: antifungal, casting, encapsulation, postharvest

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Authors: Agne Jucyte Cicine, Vytautas Abromaitis, Zita Rasuole Gasiunaite, I. Vybernaite-Lubiene, D. Overlinge, K. Vilke

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Pharmaceutical pollution in aquatic environments has become a growing concern. Various active pharmaceutical ingredient (API) residues, hormones, antibiotics, or/and psychiatric drugs, have already been discovered in different environmental compartments. Due to existing ineffective wastewater treatment technologies to remove APIs, an underestimated amount can enter the ecosystem by discharged treated wastewater. Especially, psychiatric compounds, such as carbamazepine (CBZ) and venlafaxine (VNX), persist in effluent even post-treatment. Therefore, these pharmaceuticals usually exceed safe environmental levels and pose risks to the aquatic environment, particularly to sensitive ecosystems such as the Baltic Sea. CBZ, known for its chemical stability and long biodegradation time, accumulates in the environment, threatening aquatic life and human health through the food chain. As the use of medication rises, there is an urgent need for advanced wastewater treatment to reduce pharmaceutical contamination and meet future regulatory requirements. In this study, we tested advanced oxidation technology using ozone to remove two commonly used psychiatric drugs (carbamazepine and venlafaxine) from biologically treated wastewater effluent. Additionally, general water quality parameters (suspended matter (SPM), dissolved organic carbon (DOC), chemical oxygen demand (COD), and bacterial presence were analyzed. Three wastewater treatment plants (WWTPs) representing different anthropogenic pressures were selected: 1) resort, 2) resort and residential, and 3) residential, industrial, and resort. Wastewater samples for the experiment were collected during the summer season after mechanical and biological treatment and ozonated for 5, 10, and 15 minutes. The initial dissolved ozone concentration of 7,3±0,7 mg/L was held constant during all the experiments. Pharmaceutical levels in this study exceeded the predicted no-effect concentration (PNEC) of 500 and 90 ng L⁻¹ for CBZ and VNX, respectively, in all WWTPs, except CBZ in WWTP 1. Initial CBZ contamination was found to be lower in WWTP 1 (427.4 ng L⁻¹), compared with WWTP 2 (1266.5 ng L⁻¹) and 3 (119.2 ng L⁻¹). VNX followed a similar trend with concentrations of 341.2 ng L⁻¹, 361.4 ng L⁻¹, and 390.0 ng L⁻¹, respectively, for WWTPs 1, 2, and 3. It was determined that CBZ was not detected in the effluent after 5 minutes of ozonation in any of the WWTPs. Contrarily, VNX was still detected after 5, 10, and 15 minutes of treatment with ozone, however, under the limits of quantification (LOD) (<5ng L⁻¹). Additionally, general pollution of SPM, DOC, COD, and bacterial contamination was reduced notably after 5 minutes of treatment with ozone, while no bacterial growth was obtained. Although initial pharmaceutical levels exceeded PNECs, indicating ongoing environmental risks, ozonation demonstrated high efficiency in reducing pharmaceutical and general contamination in wastewater with different pollution matrices.

Keywords: Baltic Sea, ozonation, pharmaceuticals, wastewater treatment plants

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Authors: Celeste E. van Rinsum, Sanne M. P. L. Gerards, Geert M. Rutten, Ien A. M. van de Goor, Stef P. J. Kremers

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Combined lifestyle interventions have shown to be effective in changing and maintaining behavioral lifestyle changes and reducing overweight and obesity. A lifestyle coach is expected to promote lifestyle changes in adults related to physical activity and diet. The present Coaching on Lifestyle (CooL) study examined participants’ physical activity level, dietary behavioral, and motivational changes immediately after the intervention and at 1.5 years after baseline. In CooL intervention a lifestyle coach coaches individuals from eighteen years and older with (a high risk of) obesity in group and individual sessions. In addition a process evaluation was conducted in order to examine the implementation process and to be able to interpret the changes within the participants. This action-oriented research has a pre-post design. Participants of the CooL intervention (N = 200) completed three questionnaires: at baseline, immediately after the intervention (on average after 44 weeks), and at 1.5 years after baseline. T-tests and linear regressions were conducted to test self-reported changes in physical activity (IPAQ), dietary behaviors, their quality of motivation for physical activity (BREQ-3) and for diet (REBS), body mass index (BMI), and quality of life (EQ-5D-3L). For the process evaluation, we used individual and group interviews, observations and document analyses to gain insight in the implementation process (e.g. the recruitment) and how the intervention was valued by the participants, lifestyle coaches, and referrers. The study is currently ongoing and therefore the results presented here are preliminary. On average, the participants that finished the intervention and those that have completed the long-term measurement improved their level of vigorous-intense physical activity, sedentary behavior, sugar-sweetened beverage consumption and BMI. Mixed results were observed in motivational regulation for physical activity and nutrition. Moreover, an improvement on the quality of life dimension anxiety/depression was found, also in the long-term. All the other constructs did not show significant change over time. The results of the process evaluation have shown that recruitment of clients was difficult. Participants evaluated the intervention positively and the lifestyle coaches have continuously adapted the structure and contents of the intervention throughout the study period, based on their experiences and feedback from research. Preliminary results indicate that the CooL-intervention may have beneficial effects on overweight and obese participants in terms of energy balance-related behaviors, weight reduction, and quality of life. Recruitment of participants and embedding the position of the lifestyle coach in traditional care structures is challenging.

Keywords: combined lifestyle intervention, effect evaluation, lifestyle coaching, process evaluation, overweight, the Netherlands

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Authors: Mustafa M. Donma, Orkide Donma

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Obesity is known to be associated with many clinically important diseases including metabolic syndrome (MetS). Vitamin B₁₂ plays essential roles in fat and protein metabolisms and its cooperation with vitamin B₉ is well-known. The aim of this study is to investigate the possible contributions as well as associations of these micronutrients upon obesity and MetS during childhood. A total of 128 children admitted to Namik Kemal University, Medical Faculty, Department of Pediatrics Outpatient Clinics were included into the scope of this study. The mean age±SEM of 92 morbid obese (MO) children and 36 with MetS were 118.3±3.8 months and 129.5±6.4 months, respectively (p > 0.05). The study was approved by Namık Kemal University, Medical Faculty Ethics Committee. Written informed consent forms were obtained from the parents. Demographic features and anthropometric measurements were recorded. WHO BMI-for age percentiles were used. The values above 99 percentile were defined as MO. Components of MetS [waist circumference (WC), fasting blood glucose (FBG), triacylglycerol (TRG), high density lipoprotein cholesterol (HDL-Chol), systolic pressure (SP), diastolic pressure (DP)] were determined. Routine laboratory tests were performed. Serum vitamin B₁₂ concentrations were measured using electrochemiluminescence immunoassay. Vitamin B₉ was analyzed by an immunoassay analyzer. Values for vitamin B₁₂ < 148 pmol/L, 148-221 pmol/L, > 221 pmol/L were accepted as low, borderline and normal, respectively. Vitamin B₉ levels ≤ 4 mcg/L defined deficiency state. Statistical evaluations were performed by SPSSx Version 16.0. p≤0.05 was accepted as statistical significance level. Statistically higher body mass index (BMI), WC, hip circumference (C) and neck C were calculated in MetS group compared to children with MO. No difference was noted for head C. All MetS components differed between the groups (SP, DP p < 0.001; WC, FBG, TRG p < 0.01; HDL-Chol p < 0.05). Significantly decreased vitamin B₉ and vitamin B₁₂ levels were detected (p < 0.05) in children with MetS. In both groups percentage of folate deficiency was 5.5%. No cases were below < 148 pmol/L. However, in MO group 14.3% and in MetS group 22.2% of the cases were of borderline status. In MO group B₁₂ levels were negatively correlated with BMI, WC, hip C and head C, but not with neck C. WC, hip C, head C and neck C were all negatively correlated with HDL-Chol. None of these correlations were observed in the group of children with MetS. Strong positive correlation between FBG and insulin as well as strong negative correlation between TRG and HDL-Chol detected in MO children were lost in MetS group. Deficiency state end-products of both B₉ and B₁₂ may interfere with the expected profiles of MetS components. In this study, the alterations in MetS components affected vitamin B₁₂ metabolism and also its associations with anthropometric body measurements. Further increases in vitamin B₁₂ and vitamin B₉ deficiency in MetS associated with the increased vitamin B₁₂ as well as vitamin B₉ deficiency metabolites may add to MetS parameters.

Keywords: children, cobalamin, folate, metabolic syndrome, obesity

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Authors: Sundaresan Soundararajan, Chor Ngee Tan

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Introduction: Pyogenic spondylitis, otherwise treated conservatively with long term antibiotics, would require surgical debridement and reconstruction in about 10% to 20% of cases. The classical approach adopted many surgeons have always been anterior approach in ensuring thorough and complete debridement. This, however, comes with high rates of morbidity due to the nature of its access. Direct lateral retroperitoneal approach, which has been growing in usage in degenerative lumbar diseases, has the potential in treating pyogenic spondylitis with its ease of approach and relatively low risk of complications. Aims/Objectives: The objective of this study was to evaluate the effectiveness and clinical outcome of using lateral approach surgery in the surgical management of pyogenic spondylitis of the lumbar spine. Methods: Retrospective chart analysis was done on all patients who presented with pyogenic spondylitis (lumbar discitis/vertebral osteomyelitis) and had undergone direct lateral retroperitoneal lumbar vertebral debridement and posterior instrumentation between 2014 and 2016. Data on blood loss, surgical operating time, surgical complications, clinical outcomes and fusion rates were recorded. Results: A total of 6 patients (3 male and 3 female) underwent this procedure at a single institution by a single surgeon during the defined period. One patient presented with infected implant (PLIF) and vertebral osteomyelitis while the other five presented with single level spondylodiscitis. All patients underwent lumbar debridement, iliac strut grafting and posterior instrumentation (revision of screws for infected PLIF case). The mean operating time was 308.3 mins for all 6 cases. Mean blood loss was reported at 341cc (range from 200cc to 600cc). Presenting symptom of back pain resolved in all 6 cases while 2 cases that presented with lower limb weakness had improvement of neurological deficits. One patient had dislodged strut graft while performing posterior instrumentation and needed graft revision intraoperatively. Infective markers normalized for all patients subsequently. All subjects also showed radiological evidence of fusion on 6 months follow up. Conclusions: Lateral approach in treating pyogenic spondylitis is a viable option as it allows debridement and reconstruction without the risk that comes with other anterior approaches. It allows efficient debridement, short surgical time, moderate blood loss and low risk of vascular injuries. Clinical outcomes and fusion rates by this approach also support its use as practical MIS option surgery for such infection cases.

Keywords: lateral approach, minimally invasive, pyogenic spondylitis, XLIF

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Authors: Rahul Rajak, Archana Kumari Roy

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Purpose: Development brings about structural change in the society. It is essential for socio-economic progress of the society, but it also causes pain to the people who are forced to displace from their motherland. Most of the people who are displaced due to development are poor and tribes. Development and displacement are interlinked with each other in the sense development sometimes leads to displacement of people. These studies mainly focus on socio-economic profile of villages and villagers likely to be affected by the Airport Project and they examine the issues of compensation and people’s level of satisfaction. Methodology: The study is based on Descriptive design; it is basically observational and correlation study. Primary data is used in this study. Considering the time and resource constrains, 100 people were interviewed covering socio-economic and demographic diversities from 6 out of 10 affected villages. Due to Navi Mumbai International Airport Project ten villages have to be displaced. Out of ten villages, this study is based on only six villages. These are Ulwe, Ganeshpuri, Targhar Komberbuje, Chincpada and Kopar. All six villages situated in Raigarh district under the Taluka Panvel in Maharashtra. Findings: It is revealed from the survey that there are three main castes of affected villages that are Agri, Koli, and Kradi. Entire village population of migrated person is very negligible. All three caste have main occupation are agricultural and fishing activities. People’s perception revealed that due to the establishment of the airport project, they may have more opportunities and scope of development rather than the adverse effect, but vigorously leave a motherland is psychological effect of the villagers. Research Limitation: This study is based on only six villages, the scenario of the entire ten affected villages is not explained by this research. Practical implication: The scenario of displacement and resettlement signifies more than a mere physical relocation. Compensation is not only hope for villagers, is it only give short time relief. There is a need to evolve institutions to protect and strengthen the right of Individuals. The development induced displacement exposed them to a new reality, the reality of their legality and illegality of stay on the land which belongs to the state. Originality: Mumbai has large population and high industrialized city have put land at the center of any policy implication. This paper demonstrates through the actual picture gathered from the field that how seriously the affected people suffered and are still suffering because of the land acquisition for the Navi Mumbai International Airport Project. The whole picture arise the question which is how long the government can deny the rights to farmers and agricultural laborers and remain unwilling to establish the balance between democracy and development.

Keywords: compensation, displacement, land acquisition, project affected person (PAPs), rehabilitation

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Authors: Gustavo Axel Elizalde-Velázquez

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Metformin is the first line of oral therapy to treat type II diabetes and is also employed as a treatment for other indications, such as polycystic ovary syndrome, cancer, and COVID-19. Recent data suggest it is the aspirin of the 21st century due to its antioxidant and anti-aging effects. However, increasingly current articles indicate its long-term consumption generates mitochondrial impairment. Up to date, it is known metformin increases the biogenesis of Alzheimer's amyloid peptides via up-regulating BACE1 transcription, but further information related to brain damage after its consumption is missing. Bearing in mind the above, this work aimed to establish whether or not chronic exposure to metformin may alter swimming behavior and induce neurotoxicity in Danio rerio adults. For this purpose, 250 Danio rerio grown-ups were assigned to six tanks of 50 L of capacity. Four of the six systems contained 50 fish, while the remaining two had 25 fish (≈1 male:1 female ratio). Every system with 50 fish was allocated one of the three metformin treatment concentrations (1, 20, and 40 μg/L), with one system as the control treatment. Systems with 25 fish, on the other hand, were used as positive controls for acetylcholinesterase (10 μg/L of Atrazine) and oxidative stress (3 μg/L of Atrazine). After four months of exposure, a mean of 32 fish (S.D. ± 2) per group of MET treatment survived, which were used for the evaluation of behavior with the Novel Tank test. Moreover, after the behavioral assessment, we aimed to collect the blood and brains of all fish from all treatment groups. For blood collection, fish were anesthetized with an MS-222 solution (150 mg/L), while for brain gathering, fish were euthanized using the hypothermic shock method (2–4 °C). Blood was employed to determine CASP3 activity and the percentage of apoptotic cells with the TUNEL assay, and brains were used to evaluate acetylcholinesterase activity, oxidative damage, and gene expression. After chronic exposure, MET-exposed fish exhibited less swimming activity when compared to control fish. Moreover, compared with the control group, MET significantly inhibited the activity of AChE and induced oxidative damage in the brain of fish. Concerning gene expression, MET significantly upregulated the expression of Nrf1, Nrf2, BAX, p53, BACE1, APP, PSEN1, and downregulated CASP3 and CASP9. Although MET did not overexpress the CASP3 gene, we saw a meaningful rise in the activity of this enzyme in the blood of fish exposed to MET compared to the control group, which we then confirmed by a high number of apoptotic cells in the TUNEL assay. To the best of our understanding, this is the first study that delivers evidence of oxidative impairment, apoptosis, AChE alteration, and overexpression of B- amyloid-related genes in the brain of fish exposed to metformin.

Keywords: AChE inhibition, CASP3 activity, NovelTank test, oxidative damage, TUNEL assay

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Authors: Balwinder Singh, Veerpaul Kaur Mann

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A composite material is formed by the combination of two or more phases or materials. Natural minerals-derived Basalt fiber is a kind of fiber being introduced in the polymer composite industry due to its good mechanical properties similar to synthetic fibers and low cost, environment friendly. Also, there is a rising trend towards the use of industrial wastes as fillers in polymer composites with the aim of improving the properties of the composites. The mechanical properties of the fiber-reinforced polymer composites are influenced by various factors like fiber length, fiber weight %, filler weight %, filler size, etc. Thus, a detailed study has been done on the characterization of short-chopped Basalt fiber-reinforced polymer matrix composites using fly ash as filler. Taguchi’s L9 orthogonal array has been used to develop the composites by considering fiber length (6, 9 and 12 mm), fiber weight % (25, 30 and 35 %) and filler weight % (0, 5 and 10%) as input parameters with their respective levels and a thorough analysis on the mechanical characteristics (tensile strength and impact strength) has been done using ANOVA analysis with the help of MINITAB14 software. The investigation revealed that fiber weight is the most significant parameter affecting tensile strength, followed by fiber length and fiber weight %, respectively, while impact characterization showed that fiber length is the most significant factor, followed by fly ash weight, respectively. Introduction of fly ash proved to be beneficial in both the characterization with enhanced values upto 5% fly ash weight. The present study on the natural fibres reinforced epoxy composites using fly ash as filler material to study the effect of input parameters on the tensile strength in order to maximize tensile strength of the composites. Fabrication of composites based on Taguchi L9 orthogonal array design of experiments by using three factors fibre type, fibre weight % and fly ash % with three levels of each factor. The Optimization of composition of natural fibre reinforces composites using ANOVA for obtaining maximum tensile strength on fabricated composites revealed that the natural fibres along with fly ash can be successfully used with epoxy resin to prepare polymer matrix composites with good mechanical properties. Paddy- Paddy fibre gives high elasticity to the fibre composite due to presence of approximately hexagonal structure of cellulose present in paddy fibre. Coir- Coir fibre gives less tensile strength than paddy fibre as Coir fibre is brittle in nature when it pulls breakage occurs showing less tensile strength. Banana- Banana fibre has the least tensile strength in comparison to the paddy & coir fibre due to less cellulose content. Higher fibre weight leads to reduction in tensile strength due to increased nuclei of air pockets. Increasing fly ash content reduces tensile strength due to nonbonding of fly ash particles with natural fibre. Fly ash is also not very strong as compared to the epoxy resin leading to reduction in tensile strength.

Keywords: tensile strength and epoxy resin. basalt Fiber, taguchi, polymer matrix, natural fiber

Procedia PDF Downloads 49

Authors: Mary Elizabeth Bernardin, Margie Batek, Joseph Moen, David Schnadower

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Background: Injuries due to interpersonal violence are a common reason for emergency department (ED) visits amongst the American pediatric population. Gun violence, in particular, is associated with high morbidity, mortality as well as financial costs. Patterns of pediatric ED usage may be an indicator of risk for future violence, but very little data on the topic exists. Objective: The aims of this study were to assess for frequencies of ED usage for previous interpersonal violence, mental/behavioral issues, sexual/reproductive issues and concerns for abuse in youths presenting to EDs due to physical assault injuries (PAIs) compared to firearm injuries (FIs). Methods: In this retrospective case-control study, ED charts of children ages 8-19 years who presented with injuries due to interpersonal violent encounters from 2014-2017 were reviewed. Data was collected regarding all previous ED visits for injuries due to interpersonal violence (including physical assaults and firearm injuries), mental/behavioral health visits (including depression, suicidal ideation, suicide attempt, homicidal ideation and violent behavior), sexual/reproductive health visits (including sexually transmitted infections and pregnancy related issues), and concerns for abuse (including physical abuse or domestic violence, neglect, sexual abuse, sexual assault, and intimate partner violence). Logistic regression was used to identify predictors of gun violence based on previous ED visits amongst physical assault injured versus firearm injured youths. Results: A total of 407 patients presenting to the ED for an interpersonal violent encounter were analyzed, 251 (62%) of which were due to physical assault injuries (PAIs) and 156 (38%) due to firearm injuries (FIs). The majority of both PAI and FI patients had no previous history of ED visits for violence, mental/behavioral health, sexual/reproductive health or concern for abuse (60.8% PAI, 76.3% FI). 19.2% of PAI and 13.5% of FI youths had previous ED visits for physical assault injuries (OR 0.68, P=0.24, 95% CI 0.36 to 1.29). 1.6% of PAI and 3.2% of FI youths had a history of ED visits for previous firearm injuries (OR 3.6, P=0.34, 95% CI 0.04 to 2.95). 10% of PAI and 3.8% of FI youths had previous ED visits for mental/behavioral health issues (OR 0.91, P=0.80, 95% CI 0.43 to 1.93). 10% of PAI and 2.6% of FI youths had previous ED visits due to concerns for abuse (OR 0.76, P=0.55, 95% CI 0.31 to 1.86). Conclusions: There are no statistically significant differences between physical assault-injured and firearm-injured youths in terms of ED usage for previous violent injuries, mental/behavioral health visits, sexual/reproductive health visits or concerns for abuse. However, violently injured youths in this study have more than twice the number of previous ED usage for physical assaults and mental health visits than previous literature indicates. Data comparing ED usage of victims of interpersonal violence to nonviolent ED patients is needed, but this study supports the notion that EDs may be a useful place for identification of and enrollment in interventions for youths most at risk for future violence.

Keywords: child abuse, emergency department usage, pediatric gun violence, pediatric interpersonal violence, pediatric mental health, pediatric reproductive health

Procedia PDF Downloads 235

Authors: Birendra Kumar Bista, Rhitik Bista, Prafulla Koirala, Lokendra Mandal, Nikrsh Raj Shrestha, Vivek Kattel

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Introduction: Poorly controlled diabetes is associated with cause and poor outcome of stroke. High blood sugar reduces cerebral blood flow, increases intracranial pressure, cerebral edema and neuronal death, especially among patients with poorly controlled diabetes.1 SGLT2 inhibitors are associated with 50% reduction in hemorrhagic stroke compared with placebo. SGLT2 inhibitors decrease cardiovascular events via reducing glucose, blood pressure, weight, arteriosclerosis, albuminuria and reduction of atrial fibrillation.2,3 No study has been documented in low income countries to see the role of post stroke SGLT2 inhibitors on diabetic patients at and after ICU admission. Aims: The aim of the study was to measure the 12 months outcome of diabetic patients with acute stroke admitted in ICU set up with naïve SGLT2 inhibitors add on therapy. Method: It was prospective cohort study carried out in a 250 bedded tertiary neurology care hospital at the province capital Biratnagar Nepal. Diabetic patient with acute stroke admitted in ICU from 1st January 2022 to 31st December 2022 who were not under SGLT2 inhibitors were included in the study. These patients were managed as per hospital protocol. Empagliflozin was added to the alternate enrolled patients. Empagliflozin was continued at the time of discharged and during follow up unless contraindicated. These patients were followed up for 12 months. Outcome measured were mortality, morbidity requiring readmission or hospital visit other than regular follow up, SGLT2 inhibitors related adverse events, neuropsychiatry comorbidity, functional status and biochemical parameters. Ethical permission was taken from hospital administration and ethical board. Results: Among 147 diabetic cases 68 were not treated with empagliflozin whereas 67 cases were started the SGLT2 inhibitors. HbA1c level and one year mortality was significantly low among patients on empaglifozin arm. Over a period of 12 months 427 acute stroke patients were admitted in the ICU. Out of them 44% were female, 61% hypertensive, 34% diabetic, 57% dyslipidemia, 26% smoker and with median age of 45 years. Among 427 cases 4% required neurosurgical interventions and 76% had hemorrhagic CVA. The most common reason for ICU admission was GCS<8 (51%). The median ICU stay was 5 days. ICU mortality was 21% whereas 1 year mortality was 41% with most common reason being pneumonia. Empaglifozin related adverse effect was seen in 11% most commonly lower urinary tract infection in 6%. Conclusion: Empagliflozin can safely be started among acute stroke with better Hba1C control and low mortality outcome compared to treatment without SGLT2 inhibitor.

Keywords: diabetes, ICU, mortality, SGLT2 inhibitors, stroke

Procedia PDF Downloads 60

Authors: L. C. Sánchez, L. C. Corrales, A. G. Lancheros, E. Castañeda, Y. Ariza, L. S. Fuentes, L. Sierra, J. L. Cuervo

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The importance of environment friendly alternatives in agricultural processes is the reason why the research group Ceparium, the Colegio Mayor de Cundinamarca University, Colombia, investigated the genus Bacillus and its applicability for improving crops of economic importance in Colombia. In this investigation, we presented a study in which the genus Bacillus plays a leading role as beneficial microorganism. The objective was to identify the biochemical potential of three indigenous species of Bacillus, which were able to carry out actions for biological control against pathogens and pests or promoted growth to improve productivity of crops in Colombia. The procedures were performed in three phases: first, the production of biomass of an indigenous strain and a reference strain starting from culture media for production of spores and toxins were made. Spore count was done in a Neubauer chamber, concentrations of spores of Bacillus sphaericus were prepared and a bioassay was done at the Laboratory of Entomology at the University Jorge Tadeo Lozano of Plutella xylostella larvae, insect pest of crucifers in several Colombian regions. The second phase included the extraction in the liquid state fermentation, a secondary metabolite that has antibiosis action against fungi, call iturin B, and was obtained from strains of Bacillus subtilis. The molecule was identified using High Resolution Chromatography (HPLC) and its biocontrol effect on Fusarium sp fungus causes vascular wilt in economically important plant varieties, was confirmed using testing of antagonism in Petri dish. In the third phase, an initial procedure in that let recover and identify microorganisms of the genus Bacillus from the rhizosphere in two aromatic herbs, Rosmarinus officinalis and Thymus vulgaris L. was used. Subsequently, testing of antagonism against Fusarium sp were made and an assay was done under greenhouse conditions to observe biocontrol and growth promoting action by comparing growth in length and dry weight. In the first experiment, native Bacillus sphaericus was lethal to 92% Plutella xylostella larvae in 10 DDA. In the second experiment, iturin B was identified and biological control of Fusarium sp was demonstrated. In the third study, all strains demonstrated biological control and the B14 strain identified as Bacillus megaterium increased root length and productivity of the two plants in terms of weight. It was concluded that the native microorganisms of the genus Bacillus has a great biochemical potential that provides a beneficial interactions with plants, improve their growth and development and therefore a greater impact on production.

Keywords: genus bacillus, biological control, PGPRs, biochemical potential

Procedia PDF Downloads 435

Authors: Andrew Kipp

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Student absenteeism is harmful to both the school and the absentee student. One approach to improving student absenteeism is targeting contextual factors within the students’ learning environment. However, contemporary literature has not taken an ecological agency approach to understanding student absenteeism. Ecological agency is a theoretical framework that magnifies the interplay between the environment and the actions of people within the environment. To elaborate, the person’s personal history and aspirations and the environmental conditions provide potential outlets or restrictions to their intended action. The framework provides the unique perspective of understanding absentee students’ decision-making through the affordances and constraints found in their learning environment. To that effect, the study was guided by the question, “Why do absentee students decide to engage in absenteeism in a suburban Kansas school?” A case study methodology was used to answer the research question. Four suburban, Kansas high school absentee students in the 2020-2021 school year were selected for the study. The fall 2020 semester was in a remote learning setting, and the spring 2021 semester was in an in-person learning setting. The study captured their decision-making with respect to school attendance throughsemi-structured interviews, prolonged observations, drawings, and concept maps. The data was analyzed through thematic analysis. The findings revealed that peer socialization opportunities, methods of instruction, shifts in cultural beliefs due to COVID-19, manifestations of anxiety and lack of space to escape their anxiety, social media bullying, and the inability to receive academic tutoring motivated the participants’ daily decision to either attend or miss school. The findings provided a basis to improve several institutional and classroom practices. These practices included more student-led instruction and less teacher-led instruction in both in-person and remote learning environments, promoting socialization through classroom collaboration and clubs based on emerging student interests, reducing instances of bullying through prosocial education, safe spaces for students to escape the classroom to manage their anxiety, and more opportunities for one-on-one tutoring to improve grades. The study provides an example of using the ecological agency approach to better understand the personal and environmental factors that lead to absenteeism. The study also informs educational policies and classroom practices to better promote student attendance. Further research should investigate other school contexts using the ecological agency theoretical framework to better understand the influence of the school environment on student absenteeism.

Keywords: student absenteeism, ecological agency, classroom practices, educational policy, student decision-making

Procedia PDF Downloads 144

Authors: Şefika Dilek Güven, Gülden Küçükakça

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Objective: Learning the process of interaction with patient occurs within the process of nursing education. For this reason, it is considered to provide an opportunity for questioning and rearrangement of nursing education programs by assessing attitudes of nursing students towards caring nurse-patient interaction. Method: This is a descriptive study conducted in order to assess attitudes of nursing students towards caring nurse-patient interaction. The study was conducted with 318 students who were studying at nursing department of Semra and Vefa Küçük Health High School, Nevşehir Hacı Bektaş Veli University in 2015-2016 academic year and agreed to participate in the study. “Personal Information Form” prepared by the researchers utilizing the literature and “Caring Nurse-Patient Interaction Scale (CNPIS)”, who Turkish validity and reliability were conducted by Atar and Aştı, were used in the study. The Cronbach α coefficient of CNPIS was found as 0.973 in the study. Permissions of the institution and participants were received before starting to conduct study. Significance test of the difference between two means, analysis of variance, and correlation analysis were used to assess the data. Results: Average age of nursing students participating in the study was 20.72±1.91 and 74.8% were female, and 28.0% were the fourth-year students. 52.5% of the nursing students stated that they chose nursing profession willingly, 80.2% did not have difficulty in their interactions with patients, and 84.6% did not have difficulty in their social relationships. CNPIS total mean score of nursing students was found to be 295.31±40.95. When the correlation between total CNPIS mean score of the nursing students in terms of some variables was examined; it was determined there was a significant positive correlation between ages of the nursing students and total mean score of CNPIS (r=0.184, p=0.001). CNPIS total mean score was found to be higher in female students compared to male students, in 3rd–year students compared to students studying at other years, in those choosing their profession willingly compared to those choosing their profession unwillingly, in those not having difficulty in relations with the patients compared to those having difficulty, and in those not having difficulty in social relationships compared to those having difficulty. It was determined there was a significant difference between CNPIS total mean scores in terms of the year and state of having difficulty in social relationships (p<0,005). Conclusion: Nursing students had positive attitudes towards caring nurse-patient interactions, attitudes of nursing students, who were female, studying at 3rd year, chose nursing profession willingly, did not have difficulty in patient relations, and did not have difficulty in social relationships, towards caring nurse-patient interaction were found to be more positive. In the line with these results; it can be recommended to organize activities for introducing nursing profession to the youth preparing for the university, to use methods that will increase further communication skills to nursing students during their education, to support students in terms of communication skills, and to involve activities that will strengthen their social relationships.

Keywords: nurse-patient interaction, nursing student, patient, communication

Procedia PDF Downloads 223

Authors: Antoni Grau, Yolanda Bolea, Alberto Sanfeliu

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Mobile robots can be used in many different applications, including mapping, search, rescue, reconnaissance, hazard detection, and carpet cleaning, exploration, etc. However, they are limited due to their reliance on traditional energy sources such as electricity and oil which cannot always provide a convenient energy source in all situations. In an ever more eco-conscious world, solar energy offers the most environmentally clean option of all energy sources. Electricity presents threats of pollution resulting from its production process, and oil poses a huge threat to the environment. Not only does it pose harm by the toxic emissions (for instance CO2 emissions), it produces the combustion process necessary to produce energy, but there is the ever present risk of oil spillages and damages to ecosystems. Solar energy can help to mitigate carbon emissions by replacing more carbon intensive sources of heat and power. The challenge of this work is to propose the design and the implementation of electric battery recharge stations. Those recharge docks are based on the use of renewable energy such as solar energy (with photovoltaic panels) with the object to reduce the CO2 emissions. In this paper, a comparative study of the CO2 emission productions (from the use of different energy sources: natural gas, gas oil, fuel and solar panels) in the charging process of the Segway PT batteries is carried out. To make the study with solar energy, a photovoltaic panel, and a Buck-Boost DC/DC block has been used. Specifically, the STP005S-12/Db solar panel has been used to carry out our experiments. This module is a 5Wp-photovoltaic (PV) module, configured with 36 monocrystalline cells serially connected. With those elements, a battery recharge station is made to recharge the robot batteries. For the energy storage DC/DC block, a series of ultracapacitors have been used. Due to the variation of the PV panel with the temperature and irradiation, and the non-integer behavior of the ultracapacitors as well as the non-linearities of the whole system, authors have been used a fractional control method to achieve that solar panels supply the maximum allowed power to recharge the robots in the lesser time. Greenhouse gas emissions for production of electricity vary due to regional differences in source fuel. The impact of an energy technology on the climate can be characterised by its carbon emission intensity, a measure of the amount of CO2, or CO2 equivalent emitted by unit of energy generated. In our work, the coal is the fossil energy more hazardous, providing a 53% more of gas emissions than natural gas and a 30% more than fuel. Moreover, it is remarkable that existing fossil fuel technologies produce high carbon emission intensity through the combustion of carbon-rich fuels, whilst renewable technologies such as solar produce little or no emissions during operation, but may incur emissions during manufacture. The solar energy thus can help to mitigate carbon emissions.

Keywords: autonomous robots, CO2 emissions, DC/DC buck-boost, solar energy

Procedia PDF Downloads 422

Authors: Mohamed Gazzeh, Bradley Null, Fethi Tlili, Hichem Besbes

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The burgeoning global ownership of personal vehicles has posed a significant strain on urban infrastructure, notably parking facilities, leading to traffic congestion and environmental concerns. Effective parking management systems (PMS) are indispensable for optimizing urban traffic flow and reducing emissions. The most commonly deployed systems nowadays rely on computer vision technology. This paper explores the integration of radar sensors and simulation in the context of smart parking management. We concentrate on radar sensors due to their versatility and utility in automotive applications, which extends to PMS. Additionally, radar sensors play a crucial role in driver assistance systems and autonomous vehicle development. However, the resource-intensive nature of radar data collection for algorithm development and testing necessitates innovative solutions. Simulation, particularly the monoDrive simulator, an internal development tool used by NI the Test and Measurement division of Emerson, offers a practical means to overcome this challenge. The primary objectives of this study encompass simulating radar sensors to generate a substantial dataset for algorithm development, testing, and, critically, assessing the transferability of models between simulated and real radar data. We focus on occupancy detection in parking as a practical use case, categorizing each parking space as vacant or occupied. The simulation approach using monoDrive enables algorithm validation and reliability assessment for virtual radar sensors. It meticulously designed various parking scenarios, involving manual measurements of parking spot coordinates, orientations, and the utilization of TI AWR1843 radar. To create a diverse dataset, we generated 4950 scenarios, comprising a total of 455,400 parking spots. This extensive dataset encompasses radar configuration details, ground truth occupancy information, radar detections, and associated object attributes such as range, azimuth, elevation, radar cross-section, and velocity data. The paper also addresses the intricacies and challenges of real-world radar data collection, highlighting the advantages of simulation in producing radar data for parking lot applications. We developed classification models based on Support Vector Machines (SVM) and Density-Based Spatial Clustering of Applications with Noise (DBSCAN), exclusively trained and evaluated on simulated data. Subsequently, we applied these models to real-world data, comparing their performance against the monoDrive dataset. The study demonstrates the feasibility of transferring models from a simulated environment to real-world applications, achieving an impressive accuracy score of 92% using only one radar sensor. This finding underscores the potential of radar sensors and simulation in the development of smart parking management systems, offering significant benefits for improving urban mobility and reducing environmental impact. The integration of radar sensors and simulation represents a promising avenue for enhancing smart parking management systems, addressing the challenges posed by the exponential growth in personal vehicle ownership. This research contributes valuable insights into the practicality of using simulated radar data in real-world applications and underscores the role of radar technology in advancing urban sustainability.

Keywords: autonomous vehicle simulator, FMCW radar sensors, occupancy detection, smart parking management, transferability of models

Procedia PDF Downloads 81

Authors: Dohwan Kim, Dongchoon Ryou, Pyungjong Yoo

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In public water facilities, drinking water distribution systems have played an important role along with water purification systems. The water distribution network is one of the most expensive components of water supply infrastructure systems. To improve the reliability for the drinking rate of tap water, advanced water treatment processes such as granular activated carbon and membrane filtration were used by water service providers in Korea. But, distrust of the people for tap water are still. Therefore, accurate diagnosis and condition assessment for water pipelines are required to supply the clean water. The internal corrosion of water pipe has increased as time passed. Also, the cross-sectional areas in pipe are reduced by the rust, deposits and tubercles. It is the water supply ability decreases as the increase of hydraulic pump capacity is required to supply an amount of water, such as the initial condition. If not, the poor area of water supply will be occurred by the decrease of water pressure. In order to solve these problems, water managers and engineers should be always checked for the current status of the water pipe, such as water leakage and damage of pipe. If problems occur, it should be able to respond rapidly and make an accurate estimate. In Korea, replacement and rehabilitation of aging drinking water pipes are carried out based on the circumstances of simply buried years. So, water distribution system management may not consider the entire water pipeline network. The long-term design and upgrading of a water distribution network should address economic, social, environmental, health, hydraulic, and other technical issues. This is a multi-objective problem with a high level of complexity. In this study, the thickness of the old water pipes, corrosion levels of the inner and outer surface for water pipes, basic data research (i.e. pipe types, buried years, accident record, embedded environment, etc.), specific resistance of soil, ultimate tensile strength and elongation of metal pipes, samples characteristics, and chemical composition analysis were performed about aging drinking water pipes. Samples of water pipes used in this study were cement mortar lining ductile cast iron pipe (CML-DCIP, diameter 100mm) and epoxy lining steel pipe (diameter 65 and 50mm). Buried years of CML-DCIP and epoxy lining steel pipe were respectively 32 and 23 years. The area of embedded environment was marine reclamation zone since 1940’s. The result of this study was that CML-DCIP needed replacement and epoxy lining steel pipe was still useful.

Keywords: drinking water distribution system, water supply, replacement, rehabilitation, water pipe

Procedia PDF Downloads 258

Authors: Suman Som, Abhijit Maity, Sunil B. Daschakraborty, Sujit Chaudhuri, Manik Pradhan

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Background: Helicobacter pylori is a common and important human pathogen and the primary cause of peptic ulcer disease and gastric cancer. Currently H. pylori infection is detected by both invasive and non-invasive way but the diagnostic accuracy is not up to the mark. Aim: To set up an optimal diagnostic cut-off value of 13C-Urea Breath Test to detect H. pylori infection and evaluate a novel c-PDR methodology to overcome of inconclusive grey zone. Materials and Methods: All 83 subjects first underwent upper-gastrointestinal endoscopy followed by rapid urease test and histopathology and depending on these results; we classified 49 subjects as H. pylori positive and 34 negative. After an overnight, fast patients are taken 4 gm of citric acid in 200 ml water solution and 10 minute after ingestion of the test meal, a baseline exhaled breath sample was collected. Thereafter an oral dose of 75 mg 13C-Urea dissolved in 50 ml water was given and breath samples were collected upto 90 minute for 15 minute intervals and analysed by laser based high precisional cavity enhanced spectroscopy. Results: We studied the excretion kinetics of 13C isotope enrichment (expressed as δDOB13C ‰) of exhaled breath samples and found maximum enrichment around 30 minute of H. pylori positive patients, it is due to the acid mediated stimulated urease enzyme activity and maximum acidification happened within 30 minute but no such significant isotopic enrichment observed for H. pylori negative individuals. Using Receiver Operating Characteristic (ROC) curve an optimal diagnostic cut-off value, δDOB13C ‰ = 3.14 was determined at 30 minute exhibiting 89.16% accuracy. Now to overcome grey zone problem we explore percentage dose of 13C recovered per hour, i.e. 13C-PDR (%/hr) and cumulative percentage dose of 13C recovered, i.e. c-PDR (%) in exhaled breath samples for the present 13C-UBT. We further explored the diagnostic accuracy of 13C-UBT by constructing ROC curve using c-PDR (%) values and an optimal cut-off value was estimated to be c-PDR = 1.47 (%) at 60 minute, exhibiting 100 % diagnostic sensitivity , 100 % specificity and 100 % accuracy of 13C-UBT for detection of H. pylori infection. We also elucidate the gastric emptying process of present 13C-UBT for H. pylori positive patients. The maximal emptying rate found at 36 minute and half empting time of present 13C-UBT was found at 45 minute. Conclusions: The present study exhibiting the importance of c-PDR methodology to overcome of grey zone problem in 13C-UBT for accurate determination of infection without any risk of diagnostic errors and making it sufficiently robust and novel method for an accurate and fast non-invasive diagnosis of H. pylori infection for large scale screening purposes.

Keywords: 13C-Urea breath test, c-PDR methodology, grey zone, Helicobacter pylori

Procedia PDF Downloads 301

Authors: M. Karzhauov, А. Mukhambetova, M. Sarsenova, E. Raimagambetov, V. Ogay

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Regeneration of injured articular cartilage remains one of the most difficult and unsolved problems in traumatology and orthopedics. Currently, for the treatment of cartilage defects surgical techniques for stimulation of the regeneration of cartilage in damaged joints such as multiple microperforation, mosaic chondroplasty, abrasion and microfractures is used. However, as shown by clinical practice, they can not provide a full and sustainable recovery of articular hyaline cartilage. In this regard, the current high hopes in the regeneration of cartilage defects reasonably are associated with the use of tissue engineering approaches to restore the structural and functional characteristics of damaged joints using stem cells, growth factors and biopolymers or scaffolds. The purpose of the present study was to investigate the effects of chondroinductive growth factors and synovium-derived mesenchymal stem cells (SD-MSCs) on the regeneration of cartilage defects in rabbits. SD-MSCs were isolated from the synovium membrane of Flemish giant rabbits, and expanded in complete culture medium α-MEM. Rabbit SD-MSCs were characterized by CFU-assay and by their ability to differentiate into osteoblasts, chondrocytes and adipocytes. The effects of growth factors (TGF-β1, BMP-2, BMP-4 and IGF-I) on MSC chondrogenesis were examined in micromass pellet cultures using histological and biochemical analysis. Articular cartilage defect (4mm in diameter) in the intercondylar groove of the patellofemoral joint was performed with a kit for the mosaic chondroplasty. The defect was made until subchondral bone plate. Delivery of SD-MSCs and growth factors was conducted in combination with hyaloronic acid (HA). SD-MSCs, growth factors and control groups were compared macroscopically and histologically at 10, 30, 60 and 90 days aftrer intra-articular injection. Our in vitro comparative study revealed that TGF-β1 and BMP-4 are key chondroinductive factors for both the growth and chondrogenesis of SD-MSCs. The highest effect on MSC chondrogenesis was observed with the synergistic interaction of TGF-β1 and BMP-4. In addition, biochemical analysis of the chondrogenic micromass pellets also revealed that the levels of glycosaminoglycans and DNA after combined treatment with TGF-β1 and BMP-4 was significantly higher in comparison to individual application of these factors. In vivo study showed that for complete regeneration of cartilage defects with intra-articular injection of SD-MSCs with HA takes time 90 days. However, single injection of SD-MSCs in combiantion with TGF-β1, BMP-4 and HA significantly promoted regeneration rate of the cartilage defects in rabbits. In this case, complete regeneration of cartilage defects was observed in 30 days after intra-articular injection. Thus, our in vitro and in vivo study demonstrated that combined application of rabbit SD-MSC with chondroinductive growth factors and HA results in strong synergistic effect on the chondrogenesis significantly enhancing regeneration of the damaged cartilage.

Keywords: Mesenchymal stem cells, synovium, chondroinductive factors, TGF-β1, BMP-2, BMP-4, IGF-I

Procedia PDF Downloads 306

Authors: Jean-Eric Pelet, Erhard Lick, Basma Taieb

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Purpose This research bridges the gap between sensory marketing and the use of the Internet of Things (IoT) in luxury hotels. We investigated how stimulating guests’ senses through IoT devices influenced their emotions, affective experiences, eudaimonism (well-being), and, ultimately, guest behavior. We examined potential moderating effects of gender. Design/methodology/approach We adopted a mixed method approach, combining qualitative research (semi-structured interviews) to explore hotel managers’ perspectives on the potential use of IoT in luxury hotels and quantitative research (surveying hotel guests; n=357). Findings The results showed that while the senses of smell, hearing, and sight had an impact on guests’ emotions, the senses of touch, hearing, and sight impacted guests’ affective experiences. The senses of smell and taste influenced guests’ eudaimonism. The sense of smell had a greater effect on eudaimonism and behavioral intentions among women compared to men. Originality IoT can be applied in creating customized multi-sensory hotel experiences. For example, hotels may offer unique and diverse ambiences in their rooms and suites to improve guest experiences. Research limitations/implications This study concentrated on luxury hotels located in Europe. Further research may explore the generalizability of the findings (e.g., in other cultures, comparison between high-end and low-end hotels). Practical implications Context awareness and hyper-personalization, through intensive and continuous data collection (hyper-connectivity) and real time processing, are key trends in the service industry. Therefore, big data plays a crucial role in the collection of information since it allows hoteliers to retrieve, analyze, and visualize data to provide personalized services in real time. Together with their guests, hotels may co-create customized sensory experiences. For instance, if the hotel knows about the guest’s music preferences based on social media as well as their age and gender, etc. and considers the temperature and size (standard, suite, etc.) of the guest room, this may determine the playlist of the concierge-tablet made available in the guest room. Furthermore, one may record the guest’s voice to use it for voice command purposes once the guest arrives at the hotel. Based on our finding that the sense of smell has a greater impact on eudaimonism and behavioral intentions among women than men, hotels may deploy subtler scents with lower intensities, or even different scents, for female guests in comparison to male guests.

Keywords: affective experience, emotional value, eudaimonism, hospitality industry, Internet of Things, sensory marketing

Procedia PDF Downloads 57

Authors: Tuula Nygard

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This study contributes to the pedagogical discussion on how to promote adolescents’ multiliteracies with the emphasis on information seeking and evaluation skills in contemporary media environments. The study is conducted in the school environment utilizing perspectives of educational sciences and information studies to health communication and teaching. The research focus is on the teacher role as a trusted person, who guides students to choose and use credible information sources. Evaluating the credibility of information may often be challenging. Specifically, children and adolescents may find it difficult to know what to believe and who to trust, for instance, in health and well-being communication. Thus, advanced multiliteracy skills are needed. In the school environment, trust is based on the teacher’s subject content knowledge, but also the teacher’s character and caring. Teacher’s benevolence and approachability generate trustworthiness, which lays the foundation for good interaction with students and further, for the teacher’s pedagogical authority. The study explores teachers’ perceptions of their pedagogical authority and the role of a trustee. In addition, the study examines what kind of multiliteracy practices teachers utilize in their teaching. The data will be collected by interviewing secondary school health education teachers during Spring 2019. The analysis method is a nexus analysis, which is an ethnographic research orientation. Classroom interaction as the interviewed teachers see it is scrutinized through a nexus analysis lens in order to expound a social action, where people, places, discourses, and objects are intertwined. The crucial social actions in this study are information seeking and evaluation situations, where the teacher and the students together assess the credibility of the information sources. The study is based on the hypothesis that a trustee’s opinions of credible sources and guidance in information seeking and evaluation affect students’, that is, trustors’ choices. In the school context, the teacher’s own experiences and perceptions of health-related issues cannot be brushed aside. Furthermore, adolescents are used to utilize digital technology for day-to-day information seeking, but the chosen information sources are often not very high quality. In the school, teachers are inclined to recommend familiar sources, such as health education textbook and web pages of well-known health authorities. Students, in turn, rely on the teacher’s guidance of credible information sources without using their own judgment. In terms of students’ multiliteracy competences, information seeking and evaluation tasks in health education are excellent opportunities to practice and enhance these skills. To distinguish the right information from a wrong one is particularly important in health communication because experts by experience are easy to find and their opinions are convincing. This can be addressed by employing the ideas of multiliteracy in the school subject health education and in teacher education and training.

Keywords: multiliteracies, nexus analysis, pedagogical authority, trust

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Authors: Salma Hussein, Hadia Aziz

Abstract:

Entrepreneurship plays a significant and imperative role in economic and social growth, and therefore, is stimulated and encouraged by governments and academics as a mean of creating job opportunities, innovation, and wealth. Indicative of its importance, it is essential to identify factors that encourage and promote entrepreneurial behavior. This is particularly true for developing countries where the need for entrepreneurial development is high and the resources are scarce, thus, there is a need to maximize the outcomes of investing in entrepreneurial development. Entrepreneurial education has been the center of attention and interest among researchers as it is believed to be one of the most critical factors in promoting entrepreneurship over the long run. Accordingly, the urgency to encourage entrepreneurship education and develop an enterprise culture is now a main concern in Egypt. Researchers have postulated that cognition has the potential to make a significant contribution to the study of entrepreneurship. One such contribution that future studies need to consider in entrepreneurship research is the cognitive processes that occur within the individual such as cognitive style. During the past decade, there has been an increasing interest in cognitive style among researchers and practitioners specifically in innovation and entrepreneurship field. Limited studies pay attention to study the antecedent dynamics that fuel entrepreneurial cognition to better understand its role in entrepreneurship. Moreover, while many studies were conducted on entrepreneurship education, scholars are still hesitant regarding the teachability of entrepreneurship due to the lack of clear evidence of its impact. Furthermore, the relation between cognitive style and entrepreneurial intentions, has yet to be discovered. Hence, this research aims to test the impact of entrepreneurship education on cognitive style and subsequent intention in order to evaluate whether student’s and potential entrepreneur’s cognitive styles are affected by entrepreneurial education and in turn affect their intentions. Understanding the impact of Entrepreneurship Education on ways of thinking and intention is critical for the development of effective education and training in entrepreneurship field. It is proposed that students who are exposed to entrepreneurship education programs will have a more balanced thinking style compared to those students who are not exposed. Moreover, it is hypothesized that students having a balanced cognitive style will exhibit higher levels of entrepreneurial intentions than students having an intuitive or analytical cognitive style. Finally, it is proposed that non-formal entrepreneurship education will be more positively associated with entrepreneurial intentions than will formal entrepreneurship education. The proposed methodology is a pre and post Experimental Design. The sample will include young adults, their age range from 18 till 35 years old including both students enrolled in formal entrepreneurship education programs in private universities as well as young adults who are willing to participate in a Non-Formal entrepreneurship education programs in Egypt. Attention is now given on how far individuals are analytical or intuitive in their cognitive style, to what extent it is possible to have a balanced thinking style and whether or not this can be aided by training or education. Therefore, there is an urge need for further research on entrepreneurial cognition in educational contexts.

Keywords: cognitive style, entrepreneurial intention, entrepreneurship education, experimental design

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Authors: Veronica Caprai, Katrin Schollbach, Miruna V. A. Florea, H. J. H. Brouwers

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Nowadays MSWI (Municipal Solid Waste Incineration) bottom ash (BA) produced by Waste-to-Energy (WtE) plants represents the majority of the solid residues derived from MSW incineration. Once processed, the BA is often landfilled resulting in possible environmental problems, additional costs for the plant and increasing occupation of public land. In order to limit this phenomenon, European countries such as the Netherlands aid the utilization of MSWI BA in the construction field, by providing standards about the leaching of contaminants into the environment (Dutch Soil Quality Decree). Commonly, BA has a particle size below 32 mm and a heterogeneous chemical composition, depending on its source. By washing coarser BA, an MSWI sludge is obtained. It is characterized by a high content of heavy metals, chlorides, and sulfates as well as a reduced particle size (below 0.25 mm). To lower its environmental impact, MSWI sludge is filtered or centrifuged for removing easily soluble contaminants, such as chlorides. However, the presence of heavy metals is not easily reduced, compromising its possible application. For lowering the leaching of those contaminants, the use of MSWI residues in combination with cement represents a precious option, due to the known retention of those ions into the hydrated cement matrix. Among the applications, the European standard for common cement EN 197-1:1992 allows the incorporation of up to 5% by mass of a minor additional constituent (MAC), such as fly ash or blast furnace slag but also an unspecified filler into cement. To the best of the author's knowledge, although it is widely available, it has the appropriate particle size and a chemical composition similar to cement, FC has not been investigated as possible MAC in cement production. Therefore, this paper will address the suitability of MSWI FC as MAC for CEM I 52.5 R, within a 5% maximum replacement by mass. After physical and chemical characterization of the raw materials, the crystal phases of the pastes are determined by XRD for 3 replacement levels (1%, 3%, and 5%) at different ages. Thereafter, the impact of FC on mechanical and environmental performances of cement is assessed according to EN 196-1 and the Dutch Soil Quality Decree, respectively. The investigation of the reaction products evidences the formation of layered double hydroxides (LDH), in the early stage of the reaction. Mechanically the presence of FC results in a reduction of 28 days compressive strength by 8% for a replacement of 5% wt., compared with the pure CEM I 52.5 R without any MAC. In contrast, the flexural strength is not affected by the presence of FC. Environmentally, the Dutch legislation for the leaching of contaminants for unshaped (granular) material is satisfied. Based on the collected results, FC represents a suitable candidate as MAC in cement production.

Keywords: environmental impact evaluation, Minor additional constituent, MSWI residues, X-ray diffraction crystallography

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Authors: Himanshu Kumar Gupta

Abstract:

The Jaisalmer Basin is one of the parts of the Rajasthan basin in northwestern India. The presence of five major unconformities/hiatuses of varying span i.e. at the top of Archean basement, Cambrian, Jurassic, Cretaceous, and Eocene have created the foundation for constructing a sequence stratigraphic framework. Based on basin formative tectonic events and their impact on sedimentation processes three first-order sequences have been identified in Rajasthan Basin. These are Proterozoic-Early Cambrian rift sequence, Permian to Middle-Late Eocene shelf sequence and Pleistocene - Recent sequence related to Himalayan Orogeny. The Permian to Middle Eocene I order sequence is further subdivided into three-second order sequences i.e. Permian to Late Jurassic II order sequence, Early to Late Cretaceous II order sequence and Paleocene to Middle-Late Eocene II order sequence. In this study, Late Jurassic to Early Cretaceous sequence was identified and log-based interpretation of smaller order T-R cycles have been carried out. A log profile from eastern margin to western margin (up to Shahgarh depression) has been taken. The depositional environment penetrated by the wells interpreted from log signatures gave three major facies association. The blocky and coarsening upward (funnel shape), the blocky and fining upward (bell shape) and the erratic (zig-zag) facies representing distributary mouth bar, distributary channel and marine mud facies respectively. Late Jurassic Formation (Baisakhi-Bhadasar) and Early Cretaceous Formation (Pariwar) shows a lesser number of T-R cycles in shallower and higher number of T-R cycles in deeper bathymetry. Shallowest well has 3 T-R cycles in Baisakhi-Bhadasar and 2 T-R cycles in Pariwar, whereas deeper well has 4 T-R cycles in Baisakhi-Bhadasar and 8 T-R cycles in Pariwar Formation. The Maximum Flooding surfaces observed from the stratigraphy analysis indicate major shale break (high shale content). The study area is dominated by the alternation of shale and sand lithologies, which occurs in an approximate ratio of 70:30. A seismo-geological cross section has been prepared to understand the stratigraphic thickness variation and structural disposition of the strata. The formations are quite thick to the west, the thickness of which reduces as we traverse towards the east. The folded and the faulted strata indicated the compressional tectonics followed by the extensional tectonics. Our interpretation is supported with seismic up to second order sequence indicates - Late Jurassic sequence is a Highstand Systems Tract (Baisakhi - Bhadasar formations), and the Early Cretaceous sequence is Regressive to Lowstand System Tract (Pariwar Formation).

Keywords: Jaisalmer Basin, sequence stratigraphy, system tract, T-R cycle

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Authors: Ana M. Antolín, Sandra Contreras, Francesc Medina, Didier Tichit

Abstract:

Introduction: High levels of nitrates (> 50 ppm NO3-) in drinking water are potentially risky to human health. In the recent years, the trend of nitrate concentration in groundwater is rising in the EU and other countries. Conventional catalytic nitrate reduction processes into N2 and H2O lead to some toxic intermediates and by-products, such as NO2-, NH4+, and NOx gases. Alternatively, photocatalytic nitrate removal using solar irradiation and heterogeneous catalysts is a very promising and ecofriendly technique. It has been scarcely performed and more research on highly efficient catalysts is still needed. In this work, different nanocatalysts supported on Aeroxide Titania P25 (P25) have been prepared varying: 0.5-4 % wt. Ag); Pt (2, 4 % wt.); Pt precursor (H2PtCl6/K2PtCl6); and impregnation order of both metals. Pt was chosen in order to increase the selectivity to N2 and decrease that to NO2-. Catalysts were characterized by nitrogen physisorption, X-Ray diffraction, UV-visible spectroscopy, TEM and X Ray-Photoelectron Spectroscopy. The aim was to determine the influence of the composition and the preparation method of the catalysts on the conversion and selectivity in the nitrate reduction, as well as going through an overall and better understanding of the process. Nanocatalysts synthesis: For the mono and bimetallic catalysts preparation, wise-drop wetness impregnation of the precursors (AgNO3, H2PtCl6, K2PtCl6) followed by a reduction step (NaBH4) was used to obtain the metal colloids. Results and conclusions: Denitration experiments were performed in a 350 mL PTFE batch reactor under inert standard operational conditions, ultraviolet irradiations (λ=254 nm (UV-C); λ=365 nm (UV-A)), and presence/absence of hydrogen gas as a reducing agent, contrary to most studies using oxalic or formic acid. Samples were analyzed by Ionic Chromatography. Blank experiments using respectively P25 (dark conditions), hydrogen only and UV irradiations without hydrogen demonstrated a clear influence of the presence of hydrogen on nitrate reduction. Also, they demonstrated that UV irradiation increased the selectivity to N2. Interestingly, the best activity was obtained under ultraviolet lamps, especially at a closer wavelength to visible light irradiation (λ = 365 nm) and H2. 2% Ag/P25 leaded to the highest NO3- conversion among the monometallic catalysts. However, nitrite quantities have to be diminished. On the other hand, practically no nitrate conversion was observed with the monometallics based on Pt/P25. Therefore, the amount of 2% Ag was chosen for the bimetallic catalysts. Regarding the bimetallic catalysts, it is observed that the metal impregnation order, amount and Pt precursor highly affects the results. Higher selectivity to the desirable N2 gas is obtained when Pt was firstly added, especially with K2PtCl6 as Pt precursor. This suggests that when Pt is secondly added, it covers the Ag particles, which are the most active in this reaction. It could be concluded that Ag allows the nitrate reduction step to nitrite, and Pt the nitrite reduction step toward the desirable N2 gas.

Keywords: heterogeneous catalysis, hydrogenation, nanocatalyst, nitrate removal, photocatalysis

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