Search results for: contrast enhancement technique

Authors: Khalidou Ba, Abdelkrim Chahine, Mohamed Ebn Touhami

Abstract:

A strong industrial interest is focused on the development of coatings for anticorrosion protection. In this context, phosphate composite materials are expanding strongly due to their chemical characteristics and their interesting physicochemical properties. Sol-gel coatings offer high homogeneity and purity that may lead to obtain coating presenting good adhesion to metal surface. The goal behind this work is to develop efficient coatings for corrosion protection of steel to extend its life. In this context, a sol gel process allowing to obtain thin film coatings on carbon steel with high resistance to corrosion has been developed. The optimization of several experimental parameters such as the hydrolysis time, the temperature, the coating technique, the molar ratio between precursors, the number of layers and the drying mode has been realized in order to obtain a coating showing the best anti-corrosion properties. The effect of these parameters on the microstructure and anticorrosion performance of the films sol gel coating has been investigated using different characterization methods (FTIR, XRD, Raman, XPS, SEM, Profilometer, Salt Spray Test, etc.). An optimized coating presenting good adhesion and very stable anticorrosion properties in salt spray test, which consists of a corrosive attack accelerated by an artificial salt spray consisting of a solution of 5% NaCl, pH neutral, under precise conditions of temperature (35 °C) and pressure has been obtained.

Keywords: sol gel, coating, corrosion, XPS

Procedia PDF Downloads 126

Authors: Carina Emminger, Umut D. Cakmak, Evrim Burkut, Rene Preuer, Ingrid Graz, Zoltan Major

Abstract:

Damping accompanies us daily in everyday life and is used to protect (e.g., in shoes) and make our life more comfortable (damping of unwanted motion) and calm (noise reduction). In general, damping is the absorption of energy which is either stored in the material (vibration isolation systems) or changed into heat (vibration absorbers). In case of the last, the damping mechanism can be split in active, passive, as well as semi-active (a combination of active and passive). Active damping is required to enable an almost perfect damping over the whole application range and is used, for instance, in sport cars. In contrast, passive damping is a response of the material due to external loading. Consequently, the material composition has a huge influence on the damping behavior. For elastomers, the material behavior is inherent viscoelastic, temperature, and frequency dependent. However, passive damping is not adjustable during application. Therefore, it is of importance to understand the fundamental viscoelastic behavior and the dissipation capability due to external loading. The objective of this work is to assess the limitation and applicability of viscoelastic material damping for applications in which currently coil-over shock absorbers are utilized. Coil-over shock absorbers are usually made of various mechanical parts and incorporate fluids within the damper. These shock absorbers are well-known and studied in the industry, and when needed, they can be easily adjusted during their product lifetime. In contrary, dampers made of – ideally – a single material are more resource efficient, have an easier serviceability, and are easier manufactured. However, they lack of adaptability and adjustability in service. Therefore, a case study with a remote-controlled sport car was conducted. The original shock absorbers were redesigned, and the spring-dashpot system was replaced by both an elastomer and a thermoplastic-elastomer, respectively. Here, five different formulations of elastomers were used, including a pure and an iron-particle filled thermoplastic poly(urethan) (TPU) and blends of two different poly(dimethyl siloxane) (PDMS). In addition, the TPUs were investigated as full and hollow dampers to investigate the difference between solid and structured material. To get comparative results each material formulation was comprehensively characterized, by monotonic uniaxial compression tests, dynamic thermomechanical analysis (DTMA), and rebound resilience. Moreover, the new material-based shock absorbers were compared with spring-dashpot shock absorbers. The shock absorbers were analyzed under monotonic and cyclic loading. In addition, an impact loading was applied on the remote-controlled car to measure the damping properties in operation. A servo-hydraulic high-speed linear actuator was utilized to apply the loads. The acceleration of the car and the displacement of specific measurement points were recorded while testing by a sensor and high-speed camera, respectively. The results prove that elastomers are suitable in damping applications, but they are temperature and frequency dependent. This is a limitation in applicability of viscous material damper. Feasible fields of application may be in the case of micromobility, like bicycles, e-scooters, and e-skateboards. Furthermore, the viscous material damping could be used to increase the inherent damping of a whole structure, e.g., in bicycle-frames.

Keywords: damper structures, material damping, PDMS, TPU

Procedia PDF Downloads 113

Authors: Zahid Manzoor, Shaukat Hussain Munawar, Zahid Iqbal, Imran Ahmad Khan, Abdul Aziz, Hafiz Muhammad Qasim

Abstract:

The present study was aimed to investigate the pharmacokinetics behavior and optimal dosage regimen of danofloxacin in 8 adult healthy buffaloes of local breed (Nili Ravi) following single intravenous administration at the dose of 2.5 mg/kg body weight. Plasma drug concentrations at various time intervals were measured by HPLC method. In vitro plasma protein binding was determined employing the ultrafiltration technique. The distribution and elimination of danofloxacin was rapid, as indicated by the values (Mean±SD) of distribution half-life (t1/2α = 0.25±0.09 hours) and elimination half life (t1/2β = 3.26±0.43 hours), respectively. Volume of distribution at steady state (Vss) was 1.14±0.12 L/kg, displaying its extensive distribution into various body fluids and tissues. The high value of AUC (9.80±2.14 µg/ml.hr) reflected the vast area of the body covered by drug concentration. The mean residence time was noted to be 4.78±0.52 hours. On the basis of pharmacokinetic parameters, a suitable intravenous regimen for danofloxacin in adult buffaloes would be 6.5 mg/kg to be repeated after 12 hours intervals. The present study is the foremost pharmacokinetic study of danofloxacin in the local species which would provide the valueable contribution in the local manufacturing of danofloxacin in Pakistan in future.

Keywords: danofloxacin, pharmacokinetics, plasma protein binding, buffaloes, dosage regimen

Procedia PDF Downloads 609

Authors: Aleš Florian, Lenka Ševelová

Abstract:

Complex sensitivity analysis of stresses in a concrete slab of the real type of rigid pavement made from recycled materials is performed. The computational model of the pavement is designed as a spatial (3D) model, is based on a nonlinear variant of the finite element method that respects the structural nonlinearity, enables to model different arrangements of joints, and the entire model can be loaded by the thermal load. Interaction of adjacent slabs in joints and contact of the slab and the subsequent layer are modeled with the help of special contact elements. Four concrete slabs separated by transverse and longitudinal joints and the additional structural layers and soil to the depth of about 3m are modeled. The thickness of individual layers, physical and mechanical properties of materials, characteristics of joints, and the temperature of the upper and lower surface of slabs are supposed to be random variables. The modern simulation technique Updated Latin Hypercube Sampling with 20 simulations is used. For sensitivity analysis the sensitivity coefficient based on the Spearman rank correlation coefficient is utilized. As a result, the estimates of influence of random variability of individual input variables on the random variability of principal stresses s1 and s3 in 53 points on the upper and lower surface of the concrete slabs are obtained.

Keywords: concrete, FEM, pavement, sensitivity, simulation

Procedia PDF Downloads 328

Authors: Oluwafunmibi Omotayo Fasanya, Augustine Kena Adjei

Abstract:

Controlling blood pressure is critical to reducing the risk of cardiovascular disease. However, BP control rates (systolic BP < 140 mm Hg and diastolic BP < 90 mm Hg) have declined since 2013, warranting further analysis to identify contributing factors and potential interventions. This study investigates the factors associated with the decline in blood pressure (BP) control among U.S. adults with hypertension over the past decade. Data from the U.S. National Health and Nutrition Examination Survey (NHANES) were used to assess BP control trends between 2013 and 2020. The analysis included 18,927 U.S. adults with hypertension aged 18 years and older who completed study interviews and examinations. The dataset, obtained from the cardioStatsUSA and RNHANES R packages, was merged based on survey IDs. Key variables analyzed included demographic factors, lifestyle behaviors, hypertension status, BMI, comorbidities, antihypertensive medication use, and cardiovascular disease history. The prevalence of BP control declined from 78.0% in 2013-2014 to 71.6% in 2017-2020. Non-Hispanic Whites had the highest BP control prevalence (33.6% in 2013-2014), but this declined to 26.5% by 2017-2020. In contrast, BP control among Non-Hispanic Blacks increased slightly. Younger adults (aged 18-44) exhibited better BP control, but control rates declined over time. Obesity prevalence increased, contributing to poorer BP control. Antihypertensive medication use rose from 26.1% to 29.2% across the study period. Lifestyle behaviors, such as smoking and diet, also affected BP control, with nonsmokers and those with better diets showing higher control rates. Key findings indicate significant disparities in blood pressure control across racial/ethnic groups. Non-Hispanic Black participants had consistently higher odds (OR ranging from 1.84 to 2.33) of poor blood pressure control compared to Non-Hispanic Whites, while odds among Non-Hispanic Asians varied by cycle. Younger age groups (18-44 and 45-64) showed significantly lower odds of poor blood pressure control compared to those aged 75+, highlighting better control in younger populations. Men had consistently higher odds of poor control compared to women, though this disparity slightly decreased in 2017-2020. Medical comorbidities such as diabetes and chronic kidney disease were associated with significantly higher odds of poor blood pressure control across all cycles. Participants with chronic kidney disease had particularly elevated odds (OR=5.54 in 2015-2016), underscoring the challenge of managing hypertension in these populations. Antihypertensive medication use was also linked with higher odds of poor control, suggesting potential difficulties in achieving target blood pressure despite treatment. Lifestyle factors such as alcohol consumption and physical activity showed no consistent association with blood pressure control. However, dietary quality appeared protective, with those reporting an excellent diet showing lower odds (OR=0.64) of poor control in the overall sample. Increased BMI was associated with higher odds of poor blood pressure control, particularly in the 30-35 and 35+ BMI categories during 2015-2016. The study highlights a significant decline in BP control among U.S. adults with hypertension, particularly among certain demographic groups and those with increasing obesity rates. Lifestyle behaviors, antihypertensive medication use, and socioeconomic factors all played a role in these trends.

Keywords: diabetes, blood pressure, obesity, logistic regression, odd ratio

Procedia PDF Downloads 6

Authors: Anochao Phetcharat

Abstract:

This research aims to study problems of translation basic knowledge, particularly from English into Thai. The researcher used 38 2nd-year non-English speaking students of Suratthani Rajabhat University as samples. The samples were required to translate an A4-sized article from English into Thai assigned as a part of BEN0202 Translation for Business, a requirement subject for Business English Department, which was also taught by the researcher. After completion of the translation, numerous problems were found and the research grouped them into 4 major types. The normally occurred problems in English-Thai translation works are the lack of knowledge in terms of parts of speech, word-by-word translation employment, misspellings as well as the poor knowledge in English language structure. However, this research is currently under the process of data analysis and shall be completed by the beginning of August. The researcher, nevertheless, predicts that all the above-mentioned problems, will support the researcher’s hypothesizes, that are; 1) the lack of knowledge in terms of parts of speech causes the mistranslation problem; 2) employing word-by-word translation technique hugely results in the mistranslation problem; 3) misspellings yields the mistranslation problem; and 4) the poor knowledge in English language structure also brings about translation errors. The research also predicts that, of all the aforementioned problems, the following ones are found the most, respectively: the poor knowledge in English language structure, word-by-word translation employment, the lack of knowledge in terms of parts of speech, and misspellings.

Keywords: problem, student, Thai, translation

Procedia PDF Downloads 435

Authors: Adam Modu Abbas

Abstract:

Nigeria, due to its location, size and population is very vulnerable to the impact of climate change. Little effort is however made to address most of the problems, despite the fact that sufficient understanding is made on the impact of climate change and problems emanating from it are also always being propagated. Migration, one of the resultant effects of climate change is however given less attention. This paper focuses on the climate change impact and one of resulting effects, migration and its associated problems. Purposive sampling technique was adopted in sampling 250 respondents who were mainly family members of out-migrants from Ngala and Kala-Balge LGAs of North-eastern Borno State, Nigeria. Available literatures were consulted for the types of climate change impacts. The results revealed that, climate change leads to climatic variation over the space with numerous effects on the environment such as intermittent droughts, desertification/deforestation, low water table and establishment of dams across the courses of the main sources of water supply to the Lake Chad. Many people in the study area either migrated to Cameroon’s Darrak, Lake Doi and Mayo Mbund, Lagos, Nigeria, leaving some members of their families at home. More than half of respondents indicated that the heads of the households migrated as a result of poor harvest due to diminishing or fluctuating rains/drought and/or drying of river Surbewel. It is recommended that; inter-basin water transfers should be embarked upon.

Keywords: climate, change, migration, dam, intermittent

Procedia PDF Downloads 441

Authors: Alexander David Natanson

Abstract:

This paper focuses on the effect of Sanctuary and Immigration and Customs Enforcement (ICE) policies on local economies. "Sanctuary cities" refers to municipal jurisdictions that limit their cooperation with the federal government's efforts to enforce immigration. Using county-level data from the American Community Survey and ICE data on economic indicators from 2006 to 2018, this study isolates the effects of local immigration policies on U.S. counties. The investigation is accomplished by simultaneously studying the policies' effects in counties where immigrants' families are persecuted via collaboration with Immigration and Customs Enforcement (ICE), in contrast to counties that provide protections. The analysis includes a difference-in-difference & two-way fixed effect model. Results are robust to nearest-neighbor matching, after the random assignment of treatment, after running estimations using different cutoffs for immigration policies, and with a regression discontinuity model comparing bordering counties with opposite policies. Results are also robust after restricting the data to a single-year policy adoption, using the Sun and Abraham estimator, and with event-study estimation to deal with the staggered treatment issue. In addition, the study reverses the estimation to understand what drives the decision to choose policies to detect the presence of reverse causality biases in the estimated policy impact on economic factors. The evidence demonstrates that providing protections to undocumented immigrants increases economic activity. The estimates show gains in per capita income ranging from 3.1 to 7.2, median wages between 1.7 to 2.6, and GDP between 2.4 to 4.1 percent. Regarding labor, sanctuary counties saw increases in total employment between 2.3 to 4 percent, and the unemployment rate declined from 12 to 17 percent. The data further shows that ICE policies have no statistically significant effects on income, median wages, or GDP but adverse effects on total employment, with declines from 1 to 2 percent, mostly in rural counties, and an increase in unemployment of around 7 percent in urban counties. In addition, results show a decline in the foreign-born population in ICE counties but no changes in sanctuary counties. The study also finds similar results for sanctuary counties when separating the data between urban, rural, educational attainment, gender, ethnic groups, economic quintiles, and the number of business establishments. The takeaway from this study is that institutional inclusion creates the dynamic nature of an economy, as inclusion allows for economic expansion due to the extension of fundamental freedoms to newcomers. Inclusive policies show positive effects on economic outcomes with no evident increase in population. To make sense of these results, the hypothesis and theoretical model propose that inclusive immigration policies play an essential role in conditioning the effect of immigration by decreasing uncertainties and constraints for immigrants' interaction in their communities, decreasing the cost from fear of deportation or the constant fear of criminalization and optimize their human capital.

Keywords: inclusive and exclusive institutions, post matching, fixed effect, time trend, regression discontinuity, difference-in-difference, randomization inference and sun, Abraham estimator

Procedia PDF Downloads 83

Authors: Paul Flynn, Luke O’Donnell

Abstract:

There is a pressing societal need for educators in formal and non-formal settings to develop pedagogical frameworks, programmes, and interventions that support the development of transversal skills for life beyond the classroom. These skills include communication, collaboration, interpersonal relationship building, problem-solving, and planning, and organizational skills; or lifeworld literacies encountered first hand. This is particularly true for young people aged between 15-18. This demographic represents both the future of society and those best positioned to take advantage of well-designed, structured educational supports within and across formal and non-formal settings. Secondary school history has been identified as an appropriate area of study which deftly develops many of those transversal skills so crucial to positive societal engagement. However, in the formal context, students often challenge history’s relevance to their own lived experience and dismiss it as a study option. In response to such challenges, teachers will often design stimulating lessons which are often well-received. That said, some students continue to question modern-day connections, presenting a persistent and pervasive classroom distraction. The continuing decline in numbers opting to study second-level history indicates an erosion of what should be a critical opportunity to develop all-important lifeworld literacies within formal education. In contrast, students readily acknowledge relevance in non-formal settings where many participants meaningfully engage with history by way of student-focused activities. Furthermore, many do so without predesigned pedagogical aids which support transversal skills development as embodied learning outcomes. As this paper will present, there is a dearth of work pertaining to the circular subject of history and its embodied learning outcomes, including lifeworld literacies, in formal and non-formal settings. While frequently challenging to reconcile formal (often defined by strict curricula and examination processes), and non-formal engagement with history, opportunities do exist. In the Irish context, this is exemplified by a popular university outreach programme: breaking the SEAL. This programme supports second-level history students as they fulfill curriculum requirements in completing a research study report. This report is a student-led research project pulling on communication skills, collaboration with peers and teachers, interpersonal relationships, problem-solving, and planning and organizational skills. Completion of this process has been widely recognized as excellent preparation not only for higher education (third level) but work-life demands as well. Within a formal education setting, the RSR harnesses non-formal learning virtues and exposes students to limited aspects of independent learning that relate to a professional work setting –a lifeworld literacy. Breaking the SEAL provides opportunities for students to enhance their lifeworld literacy by engaging in an independent research and learning process within the protective security of the classroom and its teacher. This paper will highlight the critical role this programme plays in preparing participating students (n=315) for life after compulsory education and presents examples of how lifeworld literacies may be developed through a scaffolded process of historical research and reporting anchored in non-formal contexts.

Keywords: history, education, literacy, transversal skills

Procedia PDF Downloads 165

Authors: Malgorzata J. Rybak-Smith, Benedicte Thiebaut, Simon Johnson, Peter Bishop, Helen E. Townley

Abstract:

Gadolinium doped titania (TiO2:Gd) nanoparticles (NPs) can be activated by X-ray radiation to generate Reactive Oxygen Species (ROS), which can be effective in killing cancer cells. As such, treatment with these NPs can be used to enhance the efficacy of conventional radiotherapy. Incorporation of the NPs in to tumour tissue will permit the extension of radiotherapy to currently untreatable tumours deep within the body, and also reduce damage to neighbouring healthy cells. In an attempt to find a fast and scalable method for the synthesis of the TiO2:Gd NPs, the use of Flame Spray Pyrolysis (FSP) was investigated. A series of TiO2 NPs were generated with 1, 2, 5 and 7 mol% gadolinium dopant. Post-synthesis, the TiO2:Gd NPs were silica-coated to improve their biocompatibility. Physico-chemical characterisation was used to determine the size and stability in aqueous suspensions of the NPs. All analysed TiO2:Gd NPs were shown to have relatively high photocatalytic activity. Furthermore, the FSP synthesized silica-coated TiO2:Gd NPs generated enhanced ROS in chemico. Studies on rhabdomyosarcoma (RMS) cell lines (RD & RH30) demonstrated that in the absence of irradiation all TiO2:Gd NPs were inert. However, application of TiO2:Gd NPs to RMS cells, followed by irradiation, showed a significant decrease in cell proliferation. Consequently, our studies showed that the X-ray-activatable TiO2:Gd NPs can be prepared by a high-throughput scalable technique to provide a novel and affordable anticancer therapy.

Keywords: cancer, gadolinium, ROS, titania nanoparticles, X-ray

Procedia PDF Downloads 429

Authors: Celso L. Fernando, Toshio Yoshii, Takahiro Tsubota

Abstract:

Understanding the causes of a road accident and predicting their occurrence is key to preventing deaths and serious injuries from road accident events. Traditional statistical methods such as the Poisson and the Logistics regressions have been used to find the association of the traffic environmental factors with the accident occurred; recently, an artificial neural network, ANN, a computational technique that learns from historical data to make a more accurate prediction, has emerged. Although the ability to make accurate predictions, the ANN has difficulty dealing with highly unbalanced attribute patterns distribution in the training dataset; in such circumstances, the ANN treats the minority group as noise. However, in the real world data, the minority group is often the group of interest; e.g., in the road traffic accident data, the events of the accident are the group of interest. This study proposes a combination of the k-means with the ANN to improve the predictive ability of the neural network model by alleviating the effect of the unbalanced distribution of the attribute patterns in the training dataset. The results show that the proposed method improves the ability of the neural network to make a prediction on a highly unbalanced distributed attribute patterns dataset; however, on an even distributed attribute patterns dataset, the proposed method performs almost like a standard neural network.

Keywords: accident risks estimation, artificial neural network, deep learning, k-mean, road safety

Procedia PDF Downloads 162

Authors: Shryas Bhurat, Aryan Vashistha, Sampreet Dinakar Nayak, Ayush Gupta

Abstract:

As the technology is advancing more towards high computational resources, there is a paradigm shift in the usage of these resources to optimize the design process. This paper discusses the usage of ‘Generative Design using Artificial Intelligence’ to build better models that adapt the operations like selection, mutation, and crossover to generate results. The human mind thinks of the simplest approach while designing an object, but the intelligence learns from the past & designs the complex optimized CAD Models. Generative Design takes the boundary conditions and comes up with multiple solutions with iterations to come up with a sturdy design with the most optimal parameter that is given, saving huge amounts of time & resources. The new production techniques that are at our disposal allow us to use additive manufacturing, 3D printing, and other innovative manufacturing techniques to save resources and design artistically engineered CAD Models. Also, this paper discusses the Genetic Algorithm, the Non-Domination technique to choose the right results using biomimicry that has evolved for current habitation for millions of years. The computer uses parametric models to generate newer models using an iterative approach & uses cloud computing to store these iterative designs. The later part of the paper compares the topology optimization technology with Generative Design that is previously being used to generate CAD Models. Finally, this paper shows the performance of algorithms and how these algorithms help in designing resource-efficient models.

Keywords: genetic algorithm, bio mimicry, generative modeling, non-dominant techniques

Procedia PDF Downloads 148

Authors: Rajani S. Pujar, Pandurangarao N. Kulkarni

Abstract:

Increased temporal masking affects the speech perception in persons with sensorineural hearing impairment especially under adverse listening conditions. This paper presents a cascaded scheme, which employs a noise reduction algorithm as well as temporal splitting of the speech signal. Earlier investigations have shown that by splitting the speech temporally and presenting alternate segments to the two ears help in reducing the effect of temporal masking. In this technique, the speech signal is processed by two fading functions, complementary to each other, and presented to left and right ears for binaural dichotic presentation. In the present study, half cosine signal is used as a fading function with crossover gain of 6 dB for the perceptual balance of loudness. Temporal splitting is combined with noise reduction algorithm to improve speech perception in the background noise. Two noise reduction schemes, namely spectral subtraction and Wiener filter are used. Listening tests were conducted on six normal-hearing subjects, with sensorineural loss simulated by adding broadband noise to the speech signal at different signal-to-noise ratios (∞, 3, 0, and -3 dB). Objective evaluation using PESQ was also carried out. The MOS score for VCV syllable /asha/ for SNR values of ∞, 3, 0, and -3 dB were 5, 4.46, 4.4 and 4.05 respectively, while the corresponding MOS scores for unprocessed speech were 5, 1.2, 0.9 and 0.65, indicating significant improvement in the perceived speech quality for the proposed scheme compared to the unprocessed speech.

Keywords: MOS, PESQ, spectral subtraction, temporal splitting, wiener filter

Procedia PDF Downloads 325

Authors: Reetika Sharma, Lalit Tejwani, Himanshu Shekhar, Arun Singhvi

Abstract:

Purpose: To describe a novel technique of trabeculectomy targeting triple modulation on wound healing to increase the overall success rate. Method: Ten eyes of 10 patients underwent trabeculectomy with subconjunctival mitomycin C (0.4mg/ml for 4 minutes) application combined with Ologen implantation subconjunctivally and subsclerally. Five of these patients underwent additional phacoemulsification with intraocular lens implantation. The Ologen implant was wet with 0.1 ml Bevacizumab. Result: All the eyes achieved target intraocular pressure (IOP), which was maintained until one year of follow-up. Two patients needed anterior chamber reformation at day two post surgery. One patient needed cataract surgery after four months of surgery and achieved target intraocular pressure on two topical antiglaucoma medicines. Conclusion: Vascular endothelial growth factor (VEGF) concentration has been seen to increase in the aqueous humor after filtration surgery. Ologen implantation helps in collagen remodelling, antifibroblastic response, and acts as a spacer. Bevacizumab augmented Ologen, in addition, targets the increased VEGF and helps in decreasing scarring. Anti-VEGF augmented Ologen in trabeculectomy with mitomycin C (MMC) hence appears to have encouraging short-term intraocular pressure control.

Keywords: ologen, anti-VEGF, trabeculectomy, scarring

Procedia PDF Downloads 184

Authors: M. Juffrie, Siti Helmyati, Toto Sudargo, B. J. Istiti Kandarina

Abstract:

Background: Iron fortification is one potential way to overcome anemia but it can cause gut microbiota imbalance. Probiotics addition can increase the growth of good gut bacteria while prebiotics can support the probiotics growth. Tempeh is rich in nutrients required for hemoglobin synthesis, such as protein, vitamin B12, vitamin C, zinc, iron and copper. Objective: To know the efficacy of fermented tempeh extract fortified with iron and synbiotic in maintain gut microbiota balance. Methods: Fermented synbiotic tempeh extract was made using Lactobacillus plantarum Dad13 and Fructo-oligosaccharides. A total of 32 anemic Wistar rats underwent the iron repletion phase then divided into 4 groups, given: 1) Fermented synbiotic tempeh extract with 50 ppm Fe/NaFeEDTA (Na), 2) Fermented synbiotic tempeh extract with 50 ppm Fe/FeSO4 (Fe), 3) Fermented synbiotic tempeh extract (St), and 4) not receive any interventions (Co). Rats were feed AIN-93 free Fe during intervention. Gut microbiota was measured with culture technique using selective media agar while hemoglobin concentration (Hb) was measured with photometric method before and after intervention. Results: There were significant increase in Hb after intervention in Na, Fe, and St, 6.85 to 11.80; 6.41 to 11.48 and 6.47 to 11.03 mg/dL, respectively (p <0.05). Co did not show increase in Hb (6.40 vs. 6.28 mg/dL). Lactobacilli increased in all groups while both of Bifidobacteria increased and E. coli decreased only in Na and St groups. Conclusion: Iron fortification of fermented synbiotic tempeh extract can increase hemoglobin concentrations in anemic animal, increase Lactobacilli and decrease E. coli. It can be an alternative solution to conduct iron fortification without deteriorate the gut microbiota.

Keywords: tempeh, synbiotic, iron, haemoglobin, gut microbiota

Procedia PDF Downloads 456

Authors: F. S. Kadhim, A. Samsuri, H. Alwan

Abstract:

Well logging records can help to answer many questions from a wide range of special interested information and basic petrophysical properties to formation evaluation of oil and gas reservoirs. The accurate calculations of porosity in carbonate reservoirs are the most challenging aspects of well log analysis. Many equations have been developed over the years based on known physical principles or on empirically derived relationships, which are used to calculate porosity, estimate lithology and water saturation; however these parameters are calculated from well logs by using modern technique in a current study. Nasiriya (NS) oilfield is one of giant oilfields in the Middle East, and the formation under study is the Mishrif carbonate formation which is the shallowest hydrocarbon bearing zone in the NS oilfield. Neurolog software (V5, 2008) was used to digitize the scanned copies of the available logs. Environmental corrections had been made as per Schlumberger charts 2005, which supplied in the Interactive Petrophysics software (IP, V3.5, 2008). Three saturation models have been used to calculate water saturation of carbonate formations, which are simple Archie equation, Dual water model, and Indonesia model. Results indicate that the Mishrif formation consists mainly of limestone, some dolomite and shale. The porosity interpretation shows that the logging tools have a good quality after making the environmental corrections. The average formation water saturation for Mishrif formation is around 0.4-0.6.This study is provided accurate behavior of petrophysical properties with depth for this formation by using modern software.

Keywords: lithology, porosity, water saturation, carbonate formation, mishrif formation

Procedia PDF Downloads 371

Authors: Noimot A. Bakare, Rotimi S. Olaleye, Bolaji O. Adeniji

Abstract:

The study examined the effectiveness of selected coping strategies for poverty alleviation among smallholder farmers in Niger State, Nigeria. Data were collected with the aid of interview schedule. A multistage random sampling technique was used to select 225 respondents from 3 geographical zones in the State. Data were analyzed using descriptive and inferential statistics. The results showed that majority (83.1%) of the respondents were within the age of 21-50 years, mostly male (76.0%) and married (77.8%). The highest educational level attained was quranic education. Findings showed that coping strategies commonly adopted by the farmers were; use of food stuff (94.2%), money savings(76.6%), reduction in expenditure(74.2%) and food consumption (65.2%). Also, there was high awareness of primary healthcare and fadama development poverty alleviation programmes by Government and non-governmental organizations. Regression model indicated a significant and positive relationship between the educational level of farmers, farm size, contact with extension and effectiveness of poverty coping strategies. Pearson correlation coefficient shows a correlation between coping strategies adopted and their effectiveness(r = 0.599, P < 0.01). However, t- test shows a significant difference between coping strategies adopted by the male and female farmers (t= -2.63, P < 0.01). It is recommended that awareness on poverty alleviation programmes aimed at improving the productivity of farming activities should be intensified while farmers should be involved in the planning and implementation of these programmes.

Keywords: coping strategies, effectiveness, farmers, poverty alleviation.

Procedia PDF Downloads 360

Authors: Houda Najeh, Mahendra Pratap Singh, Stéphane Ploix, Antoine Caucheteux, Karim Chabir, Mohamed Naceur Abdelkrim

Abstract:

Building system is highly vulnerable to different kinds of faults and human misbehaviors. Energy efficiency and user comfort are directly targeted due to abnormalities in building operation. The available fault diagnosis tools and methodologies particularly rely on rules or pure model-based approaches. It is assumed that model or rule-based test could be applied to any situation without taking into account actual testing contexts. Contextual tests with validity domain could reduce a lot of the design of detection tests. The main objective of this paper is to consider fault validity when validate the test model considering the non-modeled events such as occupancy, weather conditions, door and window openings and the integration of the knowledge of the expert on the state of the system. The concept of heterogeneous tests is combined with test validity to generate fault diagnoses. A combination of rules, range and model-based tests known as heterogeneous tests are proposed to reduce the modeling complexity. Calculation of logical diagnoses coming from artificial intelligence provides a global explanation consistent with the test result. An application example shows the efficiency of the proposed technique: an office setting at Grenoble Institute of Technology.

Keywords: heterogeneous tests, validity, building system, sensor grids, sensor fault, diagnosis, fault detection and isolation

Procedia PDF Downloads 291

Authors: Muhammad Hassan, Kemal Celebi

Abstract:

Developing a highly efficient electrochromic energy storage device with sufficient color fluctuation and significant electrochemical performance is highly desirable for practical energy-saving applications. Here, to achieve a highly stable material with a large electrochemical storage capacity, a W₁₈O₄₉ NW/Ti₃C₂Tₓ composite has been fabricated and deposited on a pre-assembled Ag and W₁₈O₄₉ NW conductive network by Langmuir-Blodgett technique. The resulting hybrid electrode composed of 15 layers of W₁₈O₄₉ NW/Ti₃C₂Tₓ exhibits an areal capacitance of 125 mF/cm², with a fast and reversible switching response. An optical modulation of 98.2% can be maintained at a current density of 5 mAcm⁻². Using this electrode, we fabricated a bifunctional symmetric electrochromic supercapacitor device having an energy density of 10.26 μWh/cm² and a power density of 0.605 mW/cm², with high capacity retention and full columbic efficiency over 4000 charge-discharge cycles. Meanwhile, the device displays remarkable electrochromic characteristics, including fast switching time (5 s for coloring and 7 s for bleaching) and a significant coloration efficiency of 116 cm²/C with good optical modulation stability. In addition, the device exhibits remarkable mechanical flexibility and fast switching while being stable over 100 bending cycles, which is promising for real-world applications.

Keywords: MXene, nanowires, supercapacitor, ion diffusion, electrochromic, coloration efficiency

Procedia PDF Downloads 74

Authors: Gregor Vidmar, Rožle Repič, Boštjan Lesar, Miha Humar

Abstract:

The study investigates the impact of cracks in surface coatings on moisture content (MC) and related fungal growth in window frames made of thermally modified (TM) and native Norway spruce using hygrothermal simulations for Ljubljana, Slovenia. Comprehensive validation against field test data confirmed the numerical model's predictions, demonstrating similar trends in MC changes over the investigated four years. Various established mould growth models (isopleth, VTT, bio hygrothermal) did not appropriately reflect differences between the spruce types because they do not consider material moisture content, leading to the main conclusion that TM spruce is more resistant to moisture-related issues. Wood's MC influences fungal decomposition, typically occurring above 25% - 30% MC, with some fungi growing at lower MC under conducive conditions. Surface coatings cannot wholly prevent water penetration, which becomes significant when the coating is damaged. This study investigates the detrimental effects of surface coating cracks on wood moisture absorption, comparing TM spruce and native spruce window frames. Simulations were conducted for undamaged and damaged coatings (from 1 mm to 9 mm wide cracks) on window profiles as well as for uncoated profiles. Sorption curves were also measured up to 95% of the relative humidity. MC was measured in the frames exposed to actual climatic conditions and compared to simulated data for model validation. The study utilizes a simplified model of the bottom frame part due to convergence issues with simulations of the whole frame. TM spruce showed about 4% lower MC content compared to native spruce. Simulations showed that a 3 mm wide crack in native spruce coatings for the north orientation poses significant moisture risks, while a 9 mm wide crack in TM spruce coatings remains acceptable furthermore in the case of uncoated TM spruce could be acceptable. In addition, it seems that large enough cracks may cause even worse moisture dynamics compared to uncoated native spruce profiles. The absorption curve comes out to be the far most influential parameter, and the next one is density. Existing mould growth models need to be upgraded to reflect wood material differences accurately. Due to the lower sorption curve of TM spruce, in reality, higher RH values are obtained under the same boundary conditions, which implies a more critical situation according to these mould growth models. Still, it does not reflect the difference in materials, especially under external exposure conditions. Even if different substrate categories in the isopleth and bio-hygrothermal model or different sensitivity material classes for standard and TM wood are used, it does not necessarily change the expected trends; thus, models with MC being the inherent part of the models should be introduced. Orientation plays a crucial role in moisture dynamics. Results show that for similar moisture dynamics, for Norway spruce, the crack could be about 2 mm wider on the south than on the north side. In contrast, for TM spruce, orientation isn't as important, compared to other material properties. The study confirms the enhanced suitability of TM spruce for window frames in terms of moisture resistance and crack tolerance in surface coatings.

Keywords: hygrothermal simulations, mould growth, surface coating, thermally modified wood, window frame

Procedia PDF Downloads 32

Authors: Mohamed Benaicha, Mahdi Allam

Abstract:

A new two stage electrochemical process as a safe, large area and low processing cost technique for the production of semi-conducting CuInSe2 (CIS) thin films is studied. CuIn precursors were first potentiostatically electrodeposited onto molybdenum substrates from an acidic thiocyanate electrolyte. In a second stage, the prepared metallic CuIn layers were used as substrate in the selenium electrochemical deposition system and subjected to a thermal treatment in vacuum atmosphere, to eliminate binary phase formation by reaction of the Cu2-x Se and InxSey selenides, leading to the formation of CuInSe2 thin film. Electrochemical selenization from aqueous electrolyte is introduced as an alternative to toxic and hazardous H2Se or Se vapor phase selenization used in physical techniques. In this study, the influence of film deposition parameters such as bath composition, temperature and potential on film properties was studied. The electrochemical, morphological, structural and compositional properties of electrodeposited thin films were characterized using various techniques. Results of Cyclic and Stripping-Cyclic Voltammetry (CV, SCV), Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray microanalysis (EDX) investigations revealed good reproducibility and homogeneity of the film composition. Thereby optimal technological parameters for the electrochemical production of CuIn, Se as precursors for CuInSe2 thin layers are determined.

Keywords: photovoltaic, CIGS, copper alloys, electrodeposition, thin films

Procedia PDF Downloads 461

Authors: Mary Esere, Mogbekeloluwa Fakokunde, Adetoun Idowu

Abstract:

Background: Working in a military setting could elicit some amount of stressful doses into ones system because of the attendant peculiar characteristics found in the military environment. Thus, this study was carried out to find out the sources of occupational stress among teachers in various Command Secondary Schools within 2 Division of Nigerian Army. Method: The study employed a survey method. Simple random sampling technique was used to select the schools in the Division. A total of 200 respondents participated in the study. Sources of Teachers’ Occupational Stress Questionnaire (STOSQ) was administered to the respondents to collect relevant data. The t-test and Analysis of Variance (ANOVA) statistics were used to test the hypotheses. Findings: From the study, it was discovered that teachers in this setting do experience occupational stress. Their major sources of stress bother on issues relating to salaries and allowances and staff welfare concerns. The findings also revealed that there were no significant differences in the sources of occupational stress among the teachers in respect to gender and marital status. Discussion: Based on these findings, it was recommended that the Appropriate Superior Authority (ASA) should reconstitute the proscribed Armed Forces Schools Management Board (AFSMB) where issues, such as staff salaries and welfare concerns for teachers working in the schools under the three services (Army, Navy, Airforce) will always be addressed. This will go a long way in enhancing the psychological well-being of the teachers.

Keywords: Nigerian army, occupational stress, sources, teachers

Procedia PDF Downloads 489

Authors: S. Ilahi, S. Almosni, F. Chouchene, M. Perrin, K. Zelazna, N. Yacoubi, R. Kudraweic, P. Rale, L. Lombez, J. F. Guillemoles, O. Durand, C. Cornet

Abstract:

Great efforts have been dedicated to obtain high quality of GaAsPN. The properties of GaAsPN have played a great part on the development of solar cells devices based in Si substrate. The incorporation of N in GaAsPN that having a band gap around of 1.7 eV is of special interest in view of growing in Si substrate. In fact, post-growth and rapid thermal annealing (RTA) could be an effective way to improve the quality of the layer. Then, the influence of growth conditions and post-growth annealing on optical and thermal parameters is considered. We have used Photothermal deflection spectroscopy PDS to investigate the impact of rapid thermal annealing on thermal and optical properties of GaAsPN. In fact, the principle of the PDS consists to illuminate the sample by a modulated monochromatic light beam. Then, the absorbed energy is converted into heat through the nonradiative recombination process. The generated thermal wave propagates into the sample and surrounding media creating a refractive-index gradient giving rise to the deflection of a laser probe beam skimming the sample surface. The incident light is assumed to be uniform, and only the sample absorbs the light. In conclusion, the results are promising revealing an improvement in absorption coefficient and thermal conductivity.

Keywords: GaAsPN absorber, photothermal defelction technique PDS, photonics on silicon, thermal conductivity

Procedia PDF Downloads 352

Authors: G. Sarojamma, K. Vendabai

Abstract:

An analysis is carried out to investigate the effect of magnetic field and heat source on the steady boundary layer flow and heat transfer of a Casson nanofluid over a vertical cylinder stretching exponentially along its radial direction. Using a similarity transformation, the governing mathematical equations, with the boundary conditions are reduced to a system of coupled, non –linear ordinary differential equations. The resulting system is solved numerically by the fourth order Runge – Kutta scheme with shooting technique. The influence of various physical parameters such as Reynolds number, Prandtl number, magnetic field, Brownian motion parameter, thermophoresis parameter, Lewis number and the natural convection parameter are presented graphically and discussed for non – dimensional velocity, temperature and nanoparticle volume fraction. Numerical data for the skin – friction coefficient, local Nusselt number and the local Sherwood number have been tabulated for various parametric conditions. It is found that the local Nusselt number is a decreasing function of Brownian motion parameter Nb and the thermophoresis parameter Nt.

Keywords: casson nanofluid, boundary layer flow, internal heat generation/absorption, exponentially stretching cylinder, heat transfer, brownian motion, thermophoresis

Procedia PDF Downloads 388

Authors: Alok Raghav, Jamal Ahmad

Abstract:

Background: Serum albumin glycation and advanced glycation end products (AGE) formation correlates in diabetes and its associated complications. Extensive modified human serum albumin is used to study the biochemical, electrochemical and functional properties in hyperglycemic environment with relevance to diabetes. We evaluate Spectroscopic, side chain modifications, amino acid analysis, biochemical and functional group properties in four glucose modified samples. Methods: A series four human serum albumin samples modified with glucose was characterized in terms of amino acid analysis, spectroscopic properties and side chain modifications. The diagnostic technique employed incorporates UV Spectroscopy, Fluorescence Spectroscopy, biochemical assays for side chain modifications, amino acid estimations, electrochemical and optical characterstic of glycated albumin. Conclusion: Glucose modified human serum albumin confers AGEs formation alters biochemical, electrochemical, optical, and functional property that depend on the reactivity of glucose and its concentration used for in-vitro glycation. A biochemical, electrochemical, optical, and functional characterization of modified albumin in-vitro produced AGE product that will be useful to interpret the complications and pathophysiological significance in diabetes.

Keywords: human serum albumin, glycated albumin, adavanced glycation end products, associated pathologies

Procedia PDF Downloads 398

Authors: Maria Isabel Garcia-Planas, Maria Victoria Garcia-Camba

Abstract:

Recent advances in cognitive neuroscience have allowed a step forward in perceiving the processes involved in learning from the point of view of the acquisition of new information or the modification of existing mental content. The evoked potentials technique reveals how basic brain processes interact to achieve adequate and flexible behaviours. The objective of this work, using evoked potentials, is to study if it is possible to distinguish if a patient suffers a specific type of learning disorder to decide the possible therapies to follow. The methodology used, is the analysis of the dynamics of different areas of the brain during a cognitive activity to find the relationships between the different areas analyzed in order to better understand the functioning of neural networks. Also, the latest advances in neuroscience have revealed the existence of different brain activity in the learning process that can be highlighted through the use of non-invasive, innocuous, low-cost and easy-access techniques such as, among others, the evoked potentials that can help to detect early possible neuro-developmental difficulties for their subsequent assessment and cure. From the study of the amplitudes and latencies of the evoked potentials, it is possible to detect brain alterations in the learning process specifically in dyscalculia, to achieve specific corrective measures for the application of personalized psycho pedagogical plans that allow obtaining an optimal integral development of the affected people.

Keywords: dyscalculia, neurodevelopment, evoked potentials, Learning disabilities, neural networks

Procedia PDF Downloads 138

Authors: Shadatul Hanom Rashid, Xiaorong Zhou

Abstract:

Hybrid sol-gel coatings are the blend of both advantages of inorganic and organic networks have been reported as environmentally friendly anti-corrosion surface pre-treatment for several metals, including aluminum alloys. In this current study, Si-Zr hybrid sol-gel coatings were synthesized from (3-glycidoxypropyl)trimethoxysilane (GPTMS), tetraethyl orthosilicate (TEOS) and zirconium(IV) propoxide (TPOZ) precursors and applied on AA6111 aluminum alloy by dip coating technique. The hybrid sol-gel coatings doped with different concentrations of cerium nitrate (Ce(NO3)3) as a corrosion inhibitor were also prepared and the effect of Ce(NO3)3 concentrations on the morphology and corrosion resistance of the coatings were examined. The surface chemistry and morphology of the hybrid sol-gel coatings were analyzed by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The corrosion behavior of the coated aluminum alloy samples was evaluated by electrochemical impedance spectroscopy (EIS). Results revealed that good corrosion resistance of hybrid sol-gel coatings were prepared from hydrolysis and condensation reactions of GPTMS, TEOS and TPOZ precursors deposited on AA6111 aluminum alloy. When the coating doped with cerium nitrate, the properties were improved significantly. The hybrid sol-gel coatings containing lower concentration of cerium nitrate offer the best inhibition performance. A proper doping concentration of Ce(NO3)3 can effectively improve the corrosion resistance of the alloy, while an excessive concentration of Ce(NO3)3 would reduce the corrosion protection properties, which is associated with defective morphology and instability of the sol-gel coatings.

Keywords: AA6111, Ce(NO3)3, corrosion, hybrid sol-gel coatings

Procedia PDF Downloads 157

Authors: Haiyan Wang, Dongyun Wang, Yongyong Yan, Richard T. Jaspers, Gang Wu

Abstract:

Mesenchymal stem cell and 3D printing-based bone tissue engineering present a promising technique to repair large-volume bone defects. Its success is highly dependent on cell attachment, spreading, osteogenic differentiation, and in vivo survival of stem cells on 3D-printed scaffolds. In this study, human salivary histatin-1 (Hst1) was utilized to enhance the interactions between human adipose-derived stem cells (hASCs) and 3D-printed β-tricalcium phosphate (β-TCP) bioceramic scaffolds. Fluorescent images showed that Hst1 significantly enhanced the adhesion of hASCs to both bioinert glass and 3D-printed β-TCP scaffold. In addition, Hst1 was associated with significantly higher proliferation and osteogenic differentiation of hASCs on 3D-printed β-TCP scaffolds. Moreover, coating 3D-printed β-TCP scaffolds with histatin significantly promotes the survival of hASCs in vivo. The ERK and p38 but not JNK signaling was found to be involved in the superior adhesion of hASCs to β-TCP scaffolds with the aid of Hst1. In conclusion, Hst1 could significantly promote the adhesion, spreading, osteogenic differentiation, and in vivo survival of hASCs on 3D-printed β-TCP scaffolds, bearing a promising application in stem cell/3D printing-based constructs for bone tissue engineering.

Keywords: 3d printing, adipose-derived stem cells, bone tissue engineering, histatin-1, osteogenesis

Procedia PDF Downloads 61

Authors: Marcela Jelicova, Anna Lierova, Zuzana Sinkorova, Radovan Metelka

Abstract:

At present, electrochemical methods are used in various research fields, especially for analysis of biological molecules. The fact offers the possibility of using the detection of oxidative damage induced indirectly by γ rays in DNA in biodosimentry. The main goal of our study is to optimize the detection of 8-hydroxyguanine by differential pulse voltammetry. The level of this stable and specific indicator of DNA damage could be determined in DNA isolated from peripheral blood lymphocytes, plasma or urine of irradiated individuals. Screen-printed carbon electrodes modified with carboxy-functionalized multi-walled carbon nanotubes were utilized for highly sensitive electrochemical detection of 8-hydroxyguanine. Electrochemical oxidation of 8-hydroxoguanine monitored by differential pulse voltammetry was found pH-dependent and the most intensive signal was recorded at pH 7. After recalculating the current density, several times higher sensitivity was attained in comparison with already published results, which were obtained using screen-printed carbon electrodes with unmodified carbon ink. Subsequently, the modified electrochemical technique was used for the detection of 8-hydroxoguanine in calf thymus DNA samples irradiated by 60Co gamma source in the dose range from 0.5 to 20 Gy using by various types of sample pretreatment and measurement conditions. This method could serve for fast retrospective quantification of absorbed dose in cases of accidental exposure to ionizing radiation and may play an important role in biodosimetry.

Keywords: biodosimetry, electrochemical detection, voltametry, 8-hydroxyguanine

Procedia PDF Downloads 273

Authors: Shubham Jaiswal

Abstract:

During modelling of many physical problems and engineering processes, fractional calculus plays an important role. Those are greatly described by fractional differential equations (FDEs). So a reliable and efficient technique to solve such types of FDEs is needed. In this article, a numerical solution of a class of fractional differential equations namely space fractional order reaction-advection dispersion equations subject to initial and boundary conditions is derived. In the proposed approach shifted Jacobi polynomials are used to approximate the solutions together with shifted Jacobi operational matrix of fractional order and spectral collocation method. The main advantage of this approach is that it converts such problems in the systems of algebraic equations which are easier to be solved. The proposed approach is effective to solve the linear as well as non-linear FDEs. To show the reliability, validity and high accuracy of proposed approach, the numerical results of some illustrative examples are reported, which are compared with the existing analytical results already reported in the literature. The error analysis for each case exhibited through graphs and tables confirms the exponential convergence rate of the proposed method.

Keywords: space fractional order linear/nonlinear reaction-advection diffusion equation, shifted Jacobi polynomials, operational matrix, collocation method, Caputo derivative

Procedia PDF Downloads 443