Search results for: multi drug resistance

Authors: Merzak Siham, Benguerine Zohra, Si Tayeb Fatima, Bouzian Chaimaa Affaf, Jou Siham, Belkessam Nafissa

Abstract:

Introduction: Medicinal plants, particularly spices, are essential for pharmacological research due to their health benefits. This study focuses on Curcuma longa, a spice recognized for its therapeutic properties. Materials and Methods: This study is based on a thorough search conducted on Google Scholar, PubMed, and ScienceDirect. From an initial selection of 25 articles, five were chosen to extract relevant information on Curcuma longa. Results and Discussions: Clinical studies have indicated that curcumin is well tolerated at doses up to 12 g/day. Its anti-rheumatic efficacy was compared to phenylbutazone in 18 individuals. Each participant received a daily dose of either 1200 mg of curcumin or 300 mg of phenylbutazone for 2 weeks. Curcumin was well tolerated at this dose and demonstrated activity comparable to phenylbutazone. Additionally, a study on 62 patients showed that curcumin sustainably relieved symptoms without toxicity. Its effects included reduced itching, lesions, and pain. In ten volunteers, administering 500 mg of curcumin for seven days resulted in a 33% decrease in lipid peroxidation, a 29% increase in HDL cholesterol, and a 12% decrease in total cholesterol. It is important to note that curcumin is a potent, selective inhibitor of phosphorylase kinase, an increased marker in psoriasis. Conclusion: Curcumin is promising as a future drug for various diseases, but its bioavailability must be improved through techniques such as nano encapsulation. Additionally, exploring chemical derivatives of curcumin could lead to more potent and targeted molecules.

Keywords: turmeric, spice, medicinal plants, pharmacological activities.

Procedia PDF Downloads 40

Authors: K. A. Chinmaya, M. Udaya Bhaskar

Abstract:

Multiphase motor drives are now a day considered for numerous applications due to the advantages that they offer when compared to their three-phase counterparts. Proper modeling of inverters and motors are important in devising an appropriate control algorithm. This paper develops a complete modeling of a five-phase inverter and five-phase space vector modulation schemes which can be used for five-phase motor drives. A novel modified algorithm is introduced which enables the sinusoidal output voltages up to certain voltage value. The waveforms of phase to neutral voltage are compared with the different modulation techniques and also different modulation indexes in terms of Low-order Harmonic (LH) voltage of 3rd and 7th present. A detailed performance evolution of existing and newly modified schemes is done in terms of Total Harmonic Distortion (THD).

Keywords: multi-phase drives, space vector modulation, voltage source inverter, low order harmonic voltages, total harmonic distortion

Procedia PDF Downloads 407

Authors: B. Daee, H. M. El Naggar

Abstract:

This paper presents an experimental study on structural performance of an innovative noise barrier consisting of poly-block, light polyurethane foam (LPF) and polyurea. This wall system (flexi-wall) is intended to be employed as a vertical extension to existing sound barriers in an accelerated construction method. To aid in the wall design, several mechanical tests were conducted on LPF specimens and two full-scale walls were then fabricated employing the same LPF material. The full-scale walls were subjected to lateral loading in order to establish their lateral resistance. A cyclic fatigue test was also performed on a full-scale flexi-wall in order to evaluate the performance of the wall under a repetitive loading condition. The result of the experiments indicated the suitability of flexi-wall in accelerated construction and confirmed that the structural performance of the wall system under lateral loading is satisfactory for the sound barrier application. The experimental results were discussed and a preliminary design procedure for application of flexi-wall in sound barrier applications was also developed.

Keywords: noise barrier, polyurethane foam, accelerated construction, full-scale experiment

Procedia PDF Downloads 295

Authors: Bhavana V. Mohite, Satish V. Patil

Abstract:

Bacterial cellulose (BC) is an alternative for plant cellulose (PC) that prevents global warming leads to preservation of nature. Although PC and BC have the same chemical structure, BC is superior with its properties like its size, purity, porosity, degree of polymerization, crystallinity and water holding capacity, thermal stability etc. On this background the present study focus production and applications of BC as antimicrobial wound dressing material. BC was produced by Gluconoacetobacter hansenii (strain NCIM 2529) under shaking condition and statistically enhanced upto 7.2 g/l from 3.0 g/l. BC was analyzed for its physico mechanical, structural and thermal characteristics. BC produced at shaking condition exhibits more suitable properties in support to its high performance applications. The potential of nano silver impregnated BC was determined for sustained release modern antimicrobial wound dressing material by swelling ratio, mechanical properties and antimicrobial activity against Staphylococcus aureus. BC in nanocomposite form with other synthetic polymer like PVA shows improvement in its properties such as swelling ratio (757% to 979%) and sustainable release of antibacterial agent. The high drug loading and release potential of BC was evidenced in support to its nature as antimicrobial wound dressing material. The nontoxic biocompatible nature of BC was confirmed by MTT assay on human epidermal cells with 90% cell viability that allows its application as a regenerative biomaterial. Thus, BC as a promising new generation antimicrobial wound dressing material was projected.

Keywords: agitated culture, biopolymer, gluconoacetobacter hansenii, nanocomposite

Procedia PDF Downloads 303

Authors: Tian Lan, Yixiang Wang, Wenxin Tai, Yilan Lyu, Zufeng Wu

Abstract:

The monaural speech enhancement task in the time-frequencydomain has a myriad of approaches, with the stacked con-volutional neural network (CNN) demonstrating superiorability in feature extraction and selection. However, usingstacked single convolutions method limits feature represen-tation capability and generalization ability. In order to solvethe aforementioned problem, we propose an attention-basedadaptive convolutional network that integrates the multi-scale convolutional operations into a operation-specific blockvia input dependent attention to adapt to complex auditoryscenes. In addition, we introduce a two-stage progressivelearning method to enlarge the receptive field without a dra-matic increase in computation burden. We conduct a series ofexperiments based on the TIMIT corpus, and the experimen-tal results prove that our proposed model is better than thestate-of-art models on all metrics.

Keywords: speech enhancement, adaptive convolu-tion, progressive learning, time-frequency domain

Procedia PDF Downloads 126

Authors: Gaspar J. Machado, Stéphane Clain, Raphael Loubère

Abstract:

The goal of the present work is to numerically study steady-state nonlinear hyperbolic equations in the context of the finite volume framework. We will consider the unidimensional Burgers' equation as the reference case for the scalar situation and the unidimensional Euler equations for the vectorial situation. We consider two approaches to solve the nonlinear equations: a time marching algorithm and a direct steady-state approach. We first develop the necessary and sufficient conditions to obtain the existence and unicity of the solution. We treat regular examples and solutions with a steady shock and to provide very-high-order finite volume approximations we implement a method based on the MOOD technology (Multi-dimensional Optimal Order Detection). The main ingredient consists in using an 'a posteriori' limiting strategy to eliminate non physical oscillations deriving from the Gibbs phenomenon while keeping a high accuracy for the smooth part.

Keywords: Euler equations, finite volume, MOOD, steady-state

Procedia PDF Downloads 278

Authors: Mahdi Asghari Ozma

Abstract:

Background and Objective:Maclurapomifera (Rafin.) Schneider, known as osage orange, is a north american native plant which has multiple applications in herbal medicine. The extract of this plant has many therapeutic effects, including antimicrobial, anti-tumor, anti-inflammation, etc., that discussed in this study. Materials and Methods: For this study, the keywords "Maclurapomifera", "osage orange, ""herbal medicine ", and "plant extract" in the databases PubMed and Google Scholar between 2002 and 2021 were searched, and 20 articles were chosen, studied and analyzed. Results: Due to the increased resistance of microbes to antibiotics, the need for antimicrobial plants is increasing. Maclurapomifera is one of the plants with antimicrobial properties that can affect all microbes, especially Gram-negative bacteria, and fungi. This plant also has anti-tumor, anti-inflammatory, anti-oxidant, anti-aging, antiviral, anti-fungal, anti-ulcerogenic, anti-diabetic, and anti-nociceptive effects, which can be used as a substance with many amazing therapeutic applications. Conclusion: These results suggest that the extract of Maclurapomifera can be used in clinical medicine as a remedial agent, which can be substituted for chemical drugs or help them in the treatment of diseases.

Keywords: maclura pomifera, osage orange, herbal medicine, plant extract

Procedia PDF Downloads 248

Authors: Sudipto Shanker Dasgupta

Abstract:

One of the largest mining companies wanted to look at health analytics for their driverless trucks. These trucks were the key to their supply chain logistics. The automated trucks had multi-level sub-assemblies which would send out sensor information. The use case that was worked on was to capture the sensor signal from the truck subcomponents and analyze the health of the trucks from repair and replacement purview. Open source software was used to stream the data into a clustered Hadoop setup in Amazon Web Services cloud and Apache Spark SQL was used to analyze the data. All of this was achieved through a 10 node amazon 32 core, 64 GB RAM setup real-time analytics was achieved on ‘300 million records’. To check the scalability of the system, the cluster was increased to 100 node setup. This talk will highlight how Open Source software was used to achieve the above use case and the insights on the high data throughput on a cloud set up.

Keywords: streaming analytics, data science, big data, Hadoop, high throughput, sensor data

Procedia PDF Downloads 407

Authors: Rajesh Kumar G

Abstract:

A challenging aspect of any clinical trial is to carefully plan the study design to meet the study objective in optimum way and to validate the assumptions made during protocol designing. And when it is a pediatric study, there is the added challenge of stringent guidelines and difficulty in recruiting the necessary subjects. Unlike adult trials, there is not much historical data available for pediatrics, which is required to validate assumptions for planning pediatric trials. Typically, pediatric studies are initiated as soon as approval is obtained for a drug to be marketed for adults, so with the adult study historical information and with the available pediatric pilot study data or simulated pediatric data, the pediatric study can be well planned. Generalizing the historical adult study for new pediatric study is a tedious task; however, it is possible by integrating various statistical techniques and utilizing the advantage of hybrid study design, which will help to achieve the study objective in a smoother way even with the presence of many constraints. This research paper will explain how well the hybrid study design can be planned along with integrated technique (SEV) to plan the pediatric study; In brief the SEV technique (Simulation, Estimation (using borrowed adult data and applying Bayesian methods)) incorporates the use of simulating the planned study data and getting the desired estimates to Validate the assumptions.This method of validation can be used to improve the accuracy of data analysis, ensuring that results are as valid and reliable as possible, which allow us to make informed decisions well ahead of study initiation. With professional precision, this technique based on the collected data allows to gain insight into best practices when using data from historical study and simulated data alike.

Keywords: adaptive design, simulation, borrowing data, bayesian model

Procedia PDF Downloads 79

Authors: Maryam Hajrezaie, Mahmood Ameen Abdulla, Nazia AbdulMajid, Maryam Zahedifard

Abstract:

Colon cancer is one of the most prevalent cancers in the world. Cancer chemoprevention is defined as the use of natural or synthetic compounds capable of inducing biological mechanisms necessary to preserve genomic fidelity. New schiff based compounds are reported to exhibit a wide spectrum of biological activities of therapeutic importance. To evaluate inhibitory properties of CdCl2(C14H21N3O2) complex on colonic aberrant crypt foci, five groups of 7-week-old male rats were used. Control group was fed with 10% Tween 20 once a day, cancer control group was intra-peritoneally injected with 15 mg/kg Azoxymethan, drug control group was injected with 15 mg/kg azoxymethan and 5-Flourouracil, experimental groups were fed with 2.5 and 5 mg/kg CdCl2(C14H21N3O2) compound each once a day. Administration of compound were found to be effectively chemoprotective. Andrographolide suppressed total colonic ACF formation up to 72% to 74%, respectively, when compared with control group. The results also showed a significant increase in glutathione peroxidase, superoxide dismutase, catalase activities and a decrease in malondialdehyde level. Immunohistochemical staining demonstrated down-regulation of PCNA protein. According to the Western blot comparison analysis, COX-2 and Bcl2 is up-regulated whilst the Bax is down-regulated. according to these data, this compound plays promising chemoprotective activity, in a model of AOM-induced in ACF.

Keywords: chemopreventive, Schiff based compound, aberrant crypt foci (ACF), immunohistochemical staining

Procedia PDF Downloads 407

Authors: A. M. Omoare, O. O. Sofowora, W. O. Oyediran

Abstract:

The study was carried out to assess the factors affecting the sustainability of rice processing and marketing in Ogun State, Nigeria. Multi-stage sampling technique was used to select one hundred and twenty (120) respondents for the study. Descriptive statistics was used to describe the objectives while hypotheses were analyzed with Pearson Product Moment Correlation. The result showed that most (85%) of the respondents was less than 50 years old and had been in rice business for more than 6 years. The majority (66.67%) of the respondents got their capitals from cooperative societies. All (100%) the respondents used rice as household food security and source of income. However, efficient rice processing and marketing were affected by inadequate manpower capacity development and inputs. There was a positive and significant relationship between socio-economic characteristics and processing techniques (p < 0.05). It is hereby recommended that extension service providers should introduce improved rice processing systems to the rice millers traders in the study area.

Keywords: sustainability, rice processing, marketing, constraints, millers traders

Procedia PDF Downloads 397

Authors: Darren Zou

Abstract:

Forecasting the stock market is a very challenging task. Various economic indicators such as GDP, exchange rates, interest rates, and unemployment have a substantial impact on the stock market. Time series models are the traditional methods used to predict stock market changes. In this paper, a machine learning method, Bayesian Additive Regression Tree (BART) is used in predicting stock market indexes based on multiple economic indicators. BART can be used to model heterogeneous treatment effects, and thereby works well when models are misspecified. It also has the capability to handle non-linear main effects and multi-way interactions without much input from financial analysts. In this research, BART is proposed to provide a reliable prediction on day-to-day stock market activities. By comparing the analysis results from BART and with time series method, BART can perform well and has better prediction capability than the traditional methods.

Keywords: BART, Bayesian, predict, stock

Procedia PDF Downloads 134

Authors: Mi Ju Choi

Abstract:

This study investigated the perception of gaming tourists toward Macau and developed a typology of gaming tourists. The 1,497 responses from tourists in Macau were collected through convenience sampling method. The dimensions of multi-culture, convenience, economy, gaming, and unsafety, were subsequently extracted as the factors of perception of gaming tourists in Macau. Cluster analysis was performed using the delineated factors (perception of tourists on Macau). Four heterogonous groups were generated, namely, gaming lovers (n = 467, 31.2%), exotic lovers (n = 509, 34.0%), reasonable budget seekers (n = 269, 18.0%), and convenience seekers (n = 252, 16.8%). Further analysis was performed to investigate any difference in gaming behavior and tourist activities. The findings are expected to contribute to the efforts of destination marketing organizations (DMOs) in establishing effective business strategies, provide a profile of gaming tourists in certain market segments, and assist DMOs and casino managers in establishing more effective marketing strategies for target markets.

Keywords: destination image, gaming tourists, Macau, segmentation

Procedia PDF Downloads 303

Authors: Zafar Iqbal, Sana Irshad Khan

Abstract:

Organic extract from newly isolated plant growth promoting fungus (PGPF) Penicillium sp EU0013 was subjected to bioassays including anti fungal (disc diffusion) cytotoxicity (brine shrimp lethality), herbicidal (Lemna minor) and nematicidal activities. Metabolite profile of the extract was also assessed using HPLC analysis with the aim to identify bioactive natural products in the extract as new drug candidate(s). The extract showed anti fungal potential against tested fungal pathogens. Growth of the Wilt pathogen Fusarium oxyosproum was inhibited up to 63% when compared to negative reference. Activity against brine shrimps was weak and mortality up to 10% was observed at concentration of 200 µg. mL-1. The extract exhibited no toxicity against Lemna minor frond at 200 µg. mL-1. Nematicidal activity was observed very potent against root knot nematode and LC50 value was calculated as 52.5 ug. mL-1 using probit analysis. Methodically assessment of metabolites profile by HPLC showed the presence of kojic acid (Rt 1.4 min) and aflatoxin B1 (Rt 5.9 min) in the mycellial extract as compared with standards. The major unidentified metabolite was eluted at Rt 8.6 along with other minor peaks. The observed high toxicity against root knot nematode was attributed to the unidentified compounds that make fungal extract worthy of further exploration for isolation and structural characterization studies for development of future commercial nematicidal compound(s).

Keywords: penicillium, nematicidal activity, metabolites, HPLC

Procedia PDF Downloads 447

Authors: Akhtar Aman, Abida Raza, Shumaila Bashir, Mehboob Alam

Abstract:

The development of efficient delivery systems remains a major concern in cancer chemotherapy as many efficacious anticancer drugs are hydrophobic and difficult to formulate. Nanomedicines based on drug-loaded amphiphilic glycol chitosan micelles offer potential advantages for the formulation of drugs such as etoposide that may improve the pharmacokinetics and reduce the formulation-related adverse effects observed with current formulations. Amphiphilic derivatives of glycol chitosan were synthesized by chemical grafting of palmitic acid N-hydroxysuccinimide and quaternization to glycol chitosan backbone. To this end, a 7.9 kDa glycol chitosan was modified by palmitoylation and quaternization, yielding a 13 kDa amphiphilic polymer. Micelles prepared from this amphiphilic polymer had a size of 162nm and were able to encapsulate up to 3 mg/ml etoposide. Pharmacokinetic results indicated that the GCPQ micelles transformed the biodistribution pattern and increased etoposide concentration in the brain significantly compared to free drugs after intravenous administration. AUC 0.5-24h showed statistically significant difference in ETP-GCPQ vs. Commercial preparation in liver (25 vs.70, p<0.001), spleen (27 vs.36, p<0.05), lungs (42 vs.136,p<0.001),kidneys(25 vs.70,p< 0.05),and brain(19 vs.9,p<0.001). ETP-GCPQ crossed the blood-brain barrier, and 4, 3.5, 2.6, 1.8, 1.7, 1.5, and 2.5 fold higher levels of etoposide were observed at 0.5, 1, 2, 4, 6, 12, and 24hrs; respectively suggesting these systems could deliver hydrophobic anticancer drugs such as etoposide to tumors but also increased their transport through the biological barriers, thus making it a good delivery system

Keywords: glycol chitosan, micelles, pharmacokinetics, tissue distribution

Procedia PDF Downloads 107

Authors: Ege Can Onal, Enver Ersen, Meltem Elitas

Abstract:

Laparoscopy is a surgical operation, well known as keyhole surgery. The operation is performed through small holes, hence, scars of a patient become much smaller, patients can recover in a short time and the hospital stay becomes shorter in comparison to an open surgery. Several tools are used at laparoscopic operations; among them, the laparoscope has a crucial role. It provides the vision during the operation, which will be the main focus in here. Since the operation area is very small, motion of the surgical tools might be limited in laparoscopic operations compared to traditional surgeries. To overcome this limitation, most of the laparoscopic tools have become more precise, dexterous, multi-functional or automated. Here, we present a robotic-assisted laparoscope that is controlled with pedals directly by a surgeon. Thus, the movement of the laparoscope might be controlled better, so there will not be a need to calibrate the camera during the operation. The need for an assistant that controls the movement of the laparoscope will be eliminated. The duration of the laparoscopic operation might be shorter since the surgeon will directly operate the camera.

Keywords: laparoscope, laparoscopy, low-cost, minimally invasive surgery, robotic-assisted surgery

Procedia PDF Downloads 344

Authors: Maryam Kiani

Abstract:

The aim of this study was to investigate the influence of carbon black additive on the properties of fly ash-based geopolymer. The geopolymer samples were prepared using fly ash as the primary source material, along with an alkali activator solution and different concentrations of carbon black additive. The effects of carbon black on the geopolymer binder were evaluated by analyzing the compressive strength, flexural strength, water absorption, and microstructural properties of the cured samples. The results revealed that the inclusion of carbon black additive significantly enhanced the mechanical properties of the geopolymer binder. The compressive and flexural strengths were found to increase with the addition of carbon black, showing improvements of up to 25% and 15%, respectively. Moreover, the water absorption of the geopolymer samples reduced due to the presence of carbon black, indicating improved resistance against water permeability. Microstructural analysis using scanning electron microscopy (SEM) revealed a more compact and homogenous structure in the geopolymer samples with carbon black. The dispersion of carbon black particles within the geopolymer matrix was observed, suggesting improved interparticle bonding and increased densification. Overall, this study demonstrates the positive impact of carbon black additive on the qualities of fly ash-based geopolymer, emphasizing its potential as an effective enhancer for geopolymer binder applications.

Keywords: fly-ash, carbon black, nanotechnology, geopolymer

Procedia PDF Downloads 116

Authors: Muhammad Ahnaf Zahin, Yaw Adu-Gyamfi

Abstract:

Bus transit is a crucial component of transportation networks, especially in urban areas. Any intelligent transportation system must have accurate real-time information on bus travel times since it minimizes waiting times for passengers at different stations along a route, improves service reliability, and significantly optimizes travel patterns. Bus agencies must enhance the quality of their information service to serve their passengers better and draw in more travelers since people waiting at bus stops are frequently anxious about when the bus will arrive at their starting point and when it will reach their destination. For solving this issue, different models have been developed for predicting bus travel times recently, but most of them are focused on smaller road networks due to their relatively subpar performance in high-density urban areas on a vast network. This paper develops a deep learning-based architecture using a single-step multi-station forecasting approach to predict average bus travel times for numerous routes, stops, and trips on a large-scale network using heterogeneous bus transit data collected from the GTFS database. Over one week, data was gathered from multiple bus routes in Saint Louis, Missouri. In this study, Gated Recurrent Unit (GRU) neural network was followed to predict the mean vehicle travel times for different hours of the day for multiple stations along multiple routes. Historical time steps and prediction horizon were set up to 5 and 1, respectively, which means that five hours of historical average travel time data were used to predict average travel time for the following hour. The spatial and temporal information and the historical average travel times were captured from the dataset for model input parameters. As adjacency matrices for the spatial input parameters, the station distances and sequence numbers were used, and the time of day (hour) was considered for the temporal inputs. Other inputs, including volatility information such as standard deviation and variance of journey durations, were also included in the model to make it more robust. The model's performance was evaluated based on a metric called mean absolute percentage error (MAPE). The observed prediction errors for various routes, trips, and stations remained consistent throughout the day. The results showed that the developed model could predict travel times more accurately during peak traffic hours, having a MAPE of around 14%, and performed less accurately during the latter part of the day. In the context of a complicated transportation network in high-density urban areas, the model showed its applicability for real-time travel time prediction of public transportation and ensured the high quality of the predictions generated by the model.

Keywords: gated recurrent unit, mean absolute percentage error, single-step forecasting, travel time prediction.

Procedia PDF Downloads 75

Authors: Sajjad Esmaeili, Robert Krause, Lukas Gerlich, Alireza Mohammadian Kia, Benjamin Uhlig

Abstract:

This investigation aims to develop the feasible and qualitative process parameters for the thin films fabrication into ultra-large through-silicon-vias (TSVs) as vertical interconnections. The focus of the study is on TSV metallization and its challenges employing new materials for the purpose of rapid signal propagation in the microsystems technology. Cobalt metal-organic chemical vapor deposition (Co-MOCVD) process enables manufacturing an adhesive and excellent conformal ultra-thin film all the way through TSVs in comparison with the conventional non-conformal physical vapor deposition (PVD) process of copper (Cu) seed layer. Therefore, this process provides a Cu seed-free layer which is capable of direct Cu electrochemical deposition (Cu-ECD) on top of it. The main challenge of this metallization module is to achieve the proper alternative seed layer with less roughness, sheet resistance and granular organic contamination (e.g. carbon) which intensify the Co corrosion under the influence of Cu electrolyte.

Keywords: Cobalt MOCVD, direct Cu electrochemical deposition (ECD), metallization technology, through-silicon-via (TSV)

Procedia PDF Downloads 162

Authors: Mohannad N. H. Al-Malichi

Abstract:

Because of its exceptional properties, graphene has become the most promising nanomaterial for the development of a new generation of advanced materials from battery electrodes to structural composites. However, current methods to meet requirements for the mass production of high-quality graphene are limited by harsh oxidation, high temperatures, and tedious processing steps. To extend the scope of the bulk production of graphene, herein, a facile, reproducible and cost-effective approach has been developed. This involved heating a specific mixture of chemical materials at an extremely low temperature (70 C) for a short period (7 minutes) to exfoliate functionalized graphene platelets with high structural integrity. The obtained graphene platelets have an average thickness of 3.86±0.71 nm and a lateral size less than ~2 µm with a low defect intensity ID/IG ~0.06. The thin film (~2 µm thick) exhibited a low surface resistance of ~0.63 Ω/sq⁻¹, confirming its high electrical conductivity. Additionally, these nanoplatelets were decorated with polar functional groups (epoxy and carboxyl groups), thus have the potential to toughen and provide multifunctional polymer nanocomposites. Moreover, such a simple method can be further exploited for the novel exfoliation of other layered two-dimensional materials such as MXenes.

Keywords: functionalized graphene nanoplatelets, high structural integrity graphene, low temperature exfoliation of graphene, functional graphene platelets

Procedia PDF Downloads 122

Authors: Anvar Atayev, Karl Steinborn, Aleksander Lovric, Saif Al-Ibadi, Jorg Fliege

Abstract:

In this paper, we present results obtained from optimising the aerodynamic performance of aerostructures in external ow. The optimisation method used was developed to efficiently handle multi-variable problems with numerous black-box objective functions and constraints. To demonstrate these capabilities, a series of CFD problems were considered; (1) a two-dimensional NACA aerofoil with three variables, (2) a two-dimensional morphing aerofoil with 17 variables, and (3) a three-dimensional morphing aeroplane tail with 33 variables. The objective functions considered were related to combinations of the mean aerodynamic coefficients, as well as their relative variations/oscillations. It was observed that for each CFD problem, an improved objective value was found. Notably, the scale-up in variables for the latter problems did not greatly hinder optimisation performance. This makes the method promising for scaled-up CFD problems, which require considerable computational resources.

Keywords: computational fluid dynamics, optimisation algorithms, aerodynamic design, engineering design

Procedia PDF Downloads 122

Authors: M. Sorahi Nobar, V. Niknam, H. Ebrahimzadeh, H. Soltanloo

Abstract:

Fusarium graminearum is one of the most destructive crop diseases in the world. Infection occurs during the flowering period in warm and humid conditions. It causes reduction in yield. Moreover, harvested grain is often contaminated with mycotoxins and its acetylated derivatives. Fusarium mycotoxines are potent inhibitor of protein synthesis, and thereby presents hazards for both human and animal health. A rapid production of reactive oxygen intermediates, primarily superoxide and hydrogen peroxide at the site of attempted infection considered as key feature underlying successful pathogen recognition. Here, we compared the time course activity of superoxide dismutase (SOD) as a first line of defenses against ROS- induced oxidative burst between FHB- resistant Sumai3 and susceptible Falat at 48, 96 and 144 hours after infection. Our results showed that Sumai3 SOD activity increased with time and reached the highest-level 4 days after infection while in susceptible cultivar Falat, SOD activity decreased during the first 96 h. after infection. Decreased was followed by an increased at 6 days after infection. According to our results rapid induction of SOD activity in resistant cultivar may play an important role in resistance against FHB in wheat.

Keywords: Fusarium graminearum, mycotoxins, resistant cultivar, superoxide dismutase

Procedia PDF Downloads 450

Authors: Eduardo Cabrera-Rode, Janet Rodriguez, Aimee Alvarez, Ragmila Echevarria, Antonio D. Reyes, Ileana Cubas-Duenas, Silvia E. Turcios, Oscar Diaz-Diaz

Abstract:

Obex is a nutritional supplement to help weight loss naturally. In addition, this supplement has a satiating effect that helps control the craving to eat between meals. The purpose of this study was to evaluate the effect of Obex in the metabolic syndrome (MS). This was an open label pilot study conducted in 30 patients with MS and ages between 29 and 60 years old. Participants received Obex, at a dose of one sachet before (30 to 45 minutes) the two main meals (lunch and dinner) daily (mean two sachets per day) for 3 months. The content of the sachets was dissolved in a glass of water or fruit juice. Obex ingredients: Açai (Euterpe oleracea Mart.) berry, inulin, Phaseolus vulgaris, Caralluma fimbriata, inositol, choline, arginine, ornitine, zinc sulfate, carnitine fumarate, methionine, calcium pantothenate, pyridoxine and folic acid. In addition to anthropometric measures and blood pressure, fasting plasma glucose, total cholesterol, triglycerides and HDL-cholesterol and insulin were determined. Insulin resistance was assessed by HOMA-IR index. Three indirect indexes were used to calculate insulin sensitivity [QUICKI index (Quantitative insulin sensitivity check index), Bennett index and Raynaud index]. Metabolic syndrome was defined according to the Joint Interim Statement (JIS) criteria. The JIS criteria require at least three of the following components: (1) abdominal obesity (waist circumference major or equal major or equal 94 cm for men or 80 cm for women), (2) triglycerides major or equal 1.7 mmol/L, (3) HDL cholesterol minor 1.03 mmol/L for men or minor 1.30 mmol/L for women, (4) systolic/diastolic blood pressure major or equal 130/85mmHg or use antihypertensive drugs, and (5) fasting plasma glucose major or equal 5.6 mmol/L or known treatment for diabetes. This study was approved by the Ethical and Research Committee of the National Institute of Endocrinology, Cuba and conducted according to the Declaration of Helsinki. Obex is registered as a food supplement in the National Institute of Nutrition and Food, Havana, Cuba. Written consent was obtained from all patients before the study. The clinical trial had been registered at ClinicalTrials.gov. After three months of treatment, 43.3% (13/30) of participants decreased the frequency of MS. Compared to baseline, Obex significantly reduced body weight, BMI, waist circumference, and waist/hip ratio and improved HDL-c (p<0.0001) and in addition to lowering blood pressure (p<0.05). After Obex intake, subjects also have shown a reduction in fasting plasma glucose (p<0.0001) and insulin sensitivity was enhanced (p=0.001). No adverse effects were seen in any of the participants during the study. In this pilot study, consumption of Obex decreased the prevalence of MS due to the improved selected components of the metabolic syndrome, indicating that further studies are warranted. Obex emerges as an effective and well tolerated treatment for preventing or delaying MS and therefore potential reduction of cardiovascular risk.

Keywords: nutritional supplement, metabolic syndrome, weight loss, insulin resistance

Procedia PDF Downloads 301

Authors: Nagi Mekhiel

Abstract:

Many applications use vector operations by applying single instruction to multiple data that map to different locations in conventional memory. Transferring data from memory is limited by access latency and bandwidth affecting the performance gain of vector processing. We present a memory system that makes all of its content available to processors in time so that processors need not to access the memory, we force each location to be available to all processors at a specific time. The data move in different orbits to become available to other processors in higher orbits at different time. We use this memory to apply parallel vector operations to data streams at first orbit level. Data processed in the first level move to upper orbit one data element at a time, allowing a processor in that orbit to apply another vector operation to deal with serial code limitations inherited in all parallel applications and interleaved it with lower level vector operations.

Keywords: Memory Organization, Parallel Processors, Serial Code, Vector Processing

Procedia PDF Downloads 273

Authors: Md. Shadab, Mariyam N. Nashid, Venkata Srikanth Meka, Thiagarajan Madheswaran

Abstract:

Naringenin (NAR), is a naturally occurring plant flavonoid, found predominantly in citrus fruits, that possesses a wide range of pharmacological properties including anti-oxidant, anti-inflammatory behaviour, cholesterol-lowering and anticarcinogenic activities. However, despite the therapeutic potential of naringenin shown in a number of animal models, its clinical development has been hindered due to its low aqueous solubility, slow dissolution rate and inefficient transport across biological membranes resulting in low bioavailability. Naringenin nanosuspension were produced using stabilizers Tween® 80 by high pressure homogenization techniques. The nanosuspensions were characterized with regard to size (photon correlation spectroscopy (PCS), size distribution, charge (zeta potential measurements), morphology, short term physical stability, dissolution profile and antioxidant potential. A nanocrystal PCS size of about 500 nm was obtained after 20 homogenization cycles at 1500 bar. The short-term stability was assessed by storage of the nanosuspensions at 4 ◦C, room temperature and 40 ◦C. Result showed that naringenin nanosuspension was physically unstable due to large fluctuations in the particle size and zeta potential after 30 days. Naringenin nanosuspension demonstrated higher drug dissolution (97.90%) compared to naringenin powder (62.76%) after 120 minutes of testing. Naringenin nanosuspension showed increased antioxidant activity compared to naringenin powder with a percentage DPPH radical scavenging activity of 49.17% and 31.45% respectively at the lowest DPPH concentration.

Keywords: bioavailability, naringenin, nanosuspension, oral delivery

Procedia PDF Downloads 329

Authors: Erfan Ghasemi, Mohammadreza Khani, Hamidreza Mahmoudi, Mohammad Ali Nilforoushzadeh, Babak Shokri, Pouria Akbartehrani

Abstract:

Given the global significance of treating infectious wounds, the goal of this study is to use spark plasma as a new treatment for infectious wounds. To generate spark plasma, a high-voltage (7 kV) and high-frequency (75 kHz) source was used. Infectious wounds in the peritoneum of mice were divided into control and plasma-treated groups at random. The plasma-treated animals received plasma radiation every 4 days for 12 days, for 60 seconds each time. On the 15th day after the first session, the wound in the plasma-treated group had completely healed. The spectra of spark plasma emission and tissue properties were studied. The mechanical resistance of the wound healed in the plasma treatment group was considerably higher than in the control group (p<0.05), according to the findings. Furthermore, histological evidence suggests that wound re-epithelialization is faster in comparison to controls. Angiogenesis and fibrosis (collagen production) were also dramatically boosted in the plasma-treated group, whereas the stage of wound healing inflammation was significantly reduced. Plasma therapy accelerated wound healing by causing considerable wound constriction. The results of this investigation show that spark plasma has an influence on the treatment of infectious wounds.

Keywords: infectious wounds, mice, spark plasma, treatment

Procedia PDF Downloads 298

Authors: Rick Evans

Abstract:

Despite over 40 years of research into why women choose not to enroll or leave undergraduate engineering programs, along with the subsequent and serious efforts to attract more women, women receiving bachelor's degrees in engineering in the US have remained disappointingly low. We know that even despite their struggles to become more welcoming and inclusive, engineering programs remain gendered, raced and classed. However, our research team has found that women who participate and indeed thrive in undergraduate engineering project teams do so in numbers that far exceed their participation in undergraduate programs. We believe part of the answer lies in the ways that project teams facilitate experiential learning, specifically providing opportunities for members to play, practice and perform. We employ a multi-case study method and assume a feminist, activist and interpretive perspective. We seek to generate concrete and context-dependent knowledge in order to explore potentially new variables and hypotheses. Our focus is to learn from those select women who are thriving. For this oral or e-poster presentation, we will focus on the results of the second of our semi-structured interviews – the learning journey interview. During this interview, we ask participants to tell us the story/ies of their participation in project teams. Our results suggest these women find joy in their experience of developing and applying engineering expertise. They experience this joy and develop their expertise in the highly patterned progression of play, practice and performance. Play is a purposeful activity in which someone enters an imaginary world, a world not yet real to them. However, this imaginary world is still very much connected to the real world, in this case, a particular kind of engineering, in that the ways of engaging are already established, codified and rule-governed. As such, these women are novices motivated to join a community of actors. Practice, better understood as practices, a count noun, is an embodied, materially interconnected collection of actions organized around the shared understandings of that community of actors. Those shared understandings reveal a social order – a particular field of engineering. No longer novices, these women begin to develop and display their emergent identities as engineers. Perform is activity meant either to demonstrate competence and/or to enable, even teach play and practice to others. As performers, these women participants become models for others. They direct play and practice, contextualizing both within a field of engineering and the specific aims of the project team community. By playing, practicing and performing engineering, women claim their identities as engineers and, equally important, have those identities acknowledged by team members. If we hope to transform our gendered, raced, classed institutions, we need to learn more about women who thrive within those institutions. We need to learn more about their processes of becoming and belonging as engineers. Our research presentation begins with a description of project teams and our multi-case study method. We then offer detailed descriptions of play, practice, and performance using the voices of women in project teams.

Keywords: engineering education, gender, identity, project teams

Procedia PDF Downloads 128

Authors: Bharatkumar Sutaria, Tejaskumar Chaudhari

Abstract:

An engine performance can be increased by minimizing losses. There are various losses observed in the engines. i.e. thermal loss, heat loss and mechanical losses. Mechanical losses are in the tune of 15 to 20 % of the overall losses. Piston ring assembly contributes the highest friction in the mechanical frictional losses. The variation of piston speed in stroke length the friction force development is not uniform. In present work, comparison has been made between theoretical and experimental friction force under different operating conditions. The experiments are performed using variable operating parameters such as load, speed, temperature and lubricants. It is found that reducing trend of friction force and friction coefficient is in good nature with mixed lubrication regime of the Stribeck curve. Overall outcome from the laboratory test performance of segmented piston ring assembly using multi-grade oil offers reasonably good results at room and elevated temperatures.

Keywords: friction force, friction coefficient, piston rings, Stribeck curve

Procedia PDF Downloads 488

Authors: Vishnu Pratap Singh Kirar

Abstract:

Artificial Neural Network (ANN) can be trained using backpropagation (BP). It is the most widely used algorithm for supervised learning with multi-layered feed-forward networks. Efficient learning by the BP algorithm is required for many practical applications. The BP algorithm calculates the weight changes of artificial neural networks, and a common approach is to use a two-term algorithm consisting of a learning rate (LR) and a momentum factor (MF). The major drawbacks of the two-term BP learning algorithm are the problems of local minima and slow convergence speeds, which limit the scope for real-time applications. Recently the addition of an extra term, called a proportional factor (PF), to the two-term BP algorithm was proposed. The third increases the speed of the BP algorithm. However, the PF term also reduces the convergence of the BP algorithm, and criteria for evaluating convergence are required to facilitate the application of the three terms BP algorithm. Although these two seem to be closely related, as described later, we summarize various improvements to overcome the drawbacks. Here we compare the different methods of convergence of the new three-term BP algorithm.

Keywords: neural network, backpropagation, local minima, fast convergence rate

Procedia PDF Downloads 503

Authors: Ekaterina Leusheva, Valentin Morenov

Abstract:

Well drilling in hard rocks is coupled with high energy demands which negates the speed of the process and thus reduces overall effectiveness. Aim of this project is to develop the technique of experimental research, which would allow to select optimal washing fluid composition while adding special hardness reducing detergent reagents. Based on the analysis of existing references and conducted experiments, technique dealing with quantitative evaluation of washing fluid weakening influence on drilled rocks was developed, which considers laboratory determination of three mud properties (density, surface tension, specific electrical resistance) and three rock properties (ultimate stress, dynamic strength, micro-hardness). Developed technique can be used in the well drilling technologies and particularly while creating new compositions of drilling muds for increased destruction effectiveness of hard rocks. It can be concluded that given technique introduces coefficient of hard rocks destruction effectiveness that allows quantitative evaluation of different drilling muds on the drilling process to be taken. Correct choice of drilling mud composition with hardness reducing detergent reagents will increase drilling penetration rate and drill meterage per bit.

Keywords: detergent reagents, drilling mud, drilling process stimulation, hard rocks

Procedia PDF Downloads 552