Search results for: differential susceptibility
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2093

Search results for: differential susceptibility

833 A Contrastive Analysis on Hausa and Yoruba Adjectival Phrases

Authors: Abubakar Maikudi

Abstract:

Contrastive analysis is the method of analyzing the structure of any two languages with a view to determining the possible differential aspects of their systems irrespective of their genetic affinity or level of development. Contrastive analysis of two languages becomes useful when it is adequately describing the sound structure and grammatical structure of two languages, with comparative statements giving emphasis to the compatible items in the two systems. This research work uses comparative analysis theory to analyze adjective and adjectival phrases in Hausa and Yorùbá languages. The Hausa language belongs to the Chadic family of the Afro-Asiatic phylum, while the Yorùbá language belongs to the Benue-Congo family of the Niger-Congo phylum. The findings of the research clearly demonstrated that there are significant similarities in the adjectival phrase constructions of the two languages, i.e., nominal (Head) and post-nominal (Post-Head) use of the adjective, predicative function of an adjective, use of the reduplicative adjective, use of the comparative and superlative adjective, etc. However, there are dissimilarities in the adjectival phrase of the two languages in gender/number agreement and pre-nominal (Post-Head) use of adjectives.

Keywords: genetic affinity, contrastive analysis, phylum, pre-head, post-head

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832 Evaluation of Occupational Exposure to Chromium for Welders of Stainless Steel

Authors: L. Musak, J. Valachova, T. Vasicko, O. Osina

Abstract:

Stainless steel is resistant to electrochemical corrosion by passivation. Welders are greatly exposed to welding fumes of toxic metals, which added to this steel. The content of chromium (Cr) is above 11.5%, Ni and Mo from 2 to 6.5%. The aim of the study was the evaluation of occupational exposure to Cr, chromosome analysis and valuation of individual susceptibility polymorphism of gene CCND1 c.870 G>A. The exposed group was consisted from 117 welders of stainless steels. The average age was 38.43 years and average exposure time 7.14 years. Smokers represented 40.17%. The control group consisted of 123 non-exposed workers with an average age of 39.74 years and time employment 16.67 years. Smokers accounted for 22.76%. Analysis of Cr in blood and urine was performed by atomic absorption spectrophotometry (AAS Varian SpectraAA 30P) with electrothermal decomposition of the sample in the graphite furnace. For the evaluation of chromosomal aberrations (CA) cytogenetic analysis of peripheral blood lymphocytes was used. Gene polymorphism was determined by PCR-RFLP reaction using appropriate primers and restriction enzymes. For statistic analysis the Mann-Whitney U-test was used. The mean Cr level in blood of exposed group was 0.095 µmol/l (0.019 min - max 0.504). No value exceeds the average normal value. The mean value Cr in urine was 7.9 µmol/mol creatinine (min 0.026 to max 19.26). The total number of CA was 1.86% in compared to 1.70% controls. (CTA-type 0.90% vs. 0.80% and CSA-type 0.96% vs. 0.90%). In the number of total CA statistical difference was observed between smokers and non-smokers of exposed group (S-1.57% vs. NS-2.04%, P<0.05). In CCND1 gene polymorphisms was observed the increasing of the total CA with wild-type allele (WT) via heterozygous to the VAR genotype (1.44% <1.82% <2.13%). A statistically higher incidence of CTA-type aberrations in variant genotypes between exposed and control groups was observed (1.22% vs. 0.59%, P <0.05). The work place is usually higher source of exposure to harmful factors. Workers need consistent and frequent health control. In assessing the risk of adverse effects of metals it is important to consider their persistence, behavior and bioavailability. Prolonged exposure to carcinogens may not manifest symptoms of poisoning, but delayed effects may occur, which resulted in a higher incidence of malignant tumors.

Keywords: CCND1, genotoxicity, polymorphism, stainless steel, welders

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831 Investigating the Fiber Content, Fiber Length, and Curing Characteristics of 3D Printed Recycled Carbon Fiber

Authors: Peng Hao Wang, Ronald Sterkenburg, Garam Kim, Yuwei He

Abstract:

As composite materials continue to gain popularity in the aerospace industry; large airframe sections made out of composite materials are becoming the standard for aerospace manufacturers. However, the heavy utilization of these composite materials also increases the importance of the recycling of these composite materials. A team of Purdue University School of Aviation and Transportation Technology (SATT) faculty and students have partnered to investigate the characteristics of 3D printed recycled carbon fiber. A prototype of a 3D printed recycled carbon fiber part was provided by an industry partner and different sections of the prototype were used to create specimens. A furnace was utilized in order to remove the polymer from the specimens and the specimen’s fiber content and fiber length was calculated from the remaining fibers. A differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) test was also conducted on the 3D printed recycled carbon fiber prototype in order to determine the prototype’s degree of cure at different locations. The data collected from this study provided valuable information in the process improvement and understanding of 3D printed recycled carbon fiber.

Keywords: 3D printed, carbon fiber, fiber content, recycling

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830 Improving Gas Separation Performance of Poly(Vinylidene Fluoride) Based Membranes Containing Ionic Liquid

Authors: S. Al-Enezi, J. Samuel, A. Al-Banna

Abstract:

Polymer based membranes are one of the low-cost technologies available for the gas separation. Three major elements required for a commercial gas separating membrane are high permeability, high selectivity, and good mechanical strength. Poly(vinylidene fluoride) (PVDF) is a commercially available fluoropolymer and a widely used membrane material in gas separation devices since it possesses remarkable thermal, chemical stability, and excellent mechanical strength. The PVDF membrane was chemically modified by soaking in different ionic liquids and dried. The thermal behavior of modified membranes was investigated by differential scanning calorimetry (DSC), and thermogravimetry (TGA), and the results clearly show the best affinity between the ionic liquid and the polymer support. The porous structure of the PVDF membranes was clearly seen in the scanning electron microscopy (SEM) images. The CO₂ permeability of blended membranes was explored in comparison with the unmodified matrix. The ionic liquid immobilized in the hydrophobic PVDF support exhibited good performance for separations of CO₂/N₂. The improved permeability of modified membrane (PVDF-IL) is attributed to the high concentration of nitrogen rich imidazolium moieties.

Keywords: PVDF, polymer membrane, gas permeability, CO₂ separation, nanotubes

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829 Application of FT-NIR Spectroscopy and Electronic Nose in On-line Monitoring of Dough Proofing

Authors: Madhuresh Dwivedi, Navneet Singh Deora, Aastha Deswal, H. N. Mishra

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FT-NIR spectroscopy and electronic nose was used to study the kinetics of dough proofing. Spectroscopy was conducted with an optic probe in the diffuse reflectance mode. The dough leavening was carried out at different temperatures (25 and 35°C) and constant RH (80%). Spectra were collected in the range of wave numbers from 12,000 to 4,000 cm-1 directly on the samples, every 5 min during proofing, up to 2 hours. NIR spectra were corrected for scatter effect and second order derivatization was done to transform the spectra. Principal component analysis (PCA) was applied for the leavening process and process kinetics was calculated. PCA was performed on data set and loadings were calculated. For leavening, four absorption zones (8,950-8,850, 7,200-6,800, 5,250-5,150 and 4,700-4,250 cm-1) were involved in describing the process. Simultaneously electronic nose was also used for understanding the development of odour compounds during fermentation. The electronic nose was able to differential the sample on the basis of aroma generation at different time during fermentation. In order to rapidly differentiate samples based on odor, a Principal component analysis is performed and successfully demonstrated in this study. The result suggests that electronic nose and FT-NIR spectroscopy can be utilized for the online quality control of the fermentation process during leavening of bread dough.

Keywords: FT-NIR, dough, e-nose, proofing, principal component analysis

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828 Mutations in rpoB, katG and inhA Genes: The Association with Resistance to Rifampicin and Isoniazid in Egyptian Mycobacterium tuberculosis Clinical Isolates

Authors: Ayman K. El Essawy, Amal M. Hosny, Hala M. Abu Shady

Abstract:

The rapid detection of TB and drug resistance, both optimizes treatment and improves outcomes. In the current study, respiratory specimens were collected from 155 patients. Conventional susceptibility testing and MIC determination were performed for rifampicin (RIF) and isoniazid (INH). Genotype MTBDRplus assay, which is a molecular genetic assay based on the DNA-STRIP technology and specific gene sequencing with primers for rpoB, KatG, and mab-inhA genes were used to detect mutations associated with resistance to rifampicin and isoniazid. In comparison to other categories, most of rifampicin resistant (61.5%) and isoniazid resistant isolates (47.1%) were from patients relapsed in treatment. The genotypic profile (using Genotype MTBDRplus assay) of multi-drug resistant (MDR) isolates showed missing of katG wild type 1 (WT1) band and appearance of mutation band katG MUT2. For isoniazid mono-resistant isolates, 80% showed katG MUT1, 20% showed katG MUT1, and inhA MUT1, 20% showed only inhA MUT1. Accordingly, 100% of isoniazid resistant strains were detected by this assay. Out of 17 resistant strains, 16 had mutation bands for katG distinguished high resistance to isoniazid. The assay could clearly detect rifampicin resistance among 66.7% of MDR isolates that showed mutation band rpoB MUT3 while 33.3% of them were considered as unknown. One mono-resistant rifampicin isolate did not show rifampicin mutation bands by Genotype MTBDRplus assay, but it showed an unexpected mutation in Codon 531 of rpoB by DNA sequence analysis. Rifampicin resistance in this strain could be associated with a mutation in codon 531 of rpoB (based on molecular sequencing), and Genotype MTBDRplus assay could not detect the associated mutation. If the results of Genotype MTBDRplus assay and sequencing were combined, this strain shows hetero-resistance pattern. Gene sequencing of eight selected isolates, previously tested by Genotype MTBDRplus assay, could detect resistance mutations mainly in codon 315 (katG gene), position -15 in inhA promotes gene for isoniazid resistance and codon 531 (rpoB gene) for rifampicin resistance. Genotyping techniques allow distinguishing between recurrent cases of reinfection or reactivation and supports epidemiological studies.

Keywords: M. tuberculosis, rpoB, KatG, inhA, genotype MTBDRplus

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827 Risk Factors for Severe Typhoid Fever in Children: A French Retrospective Study about 78 Cases from 2000-2017 in Six Parisian Hospitals

Authors: Jonathan Soliman, Thomas Cavasino, Virginie Pommelet, Lahouari Amor, Pierre Mornand, Simon Escoda, Nina Droz, Soraya Matczak, Julie Toubiana, François Angoulvant, Etienne Carbonnelle, Albert Faye, Loic de Pontual, Luu-Ly Pham

Abstract:

Background: Typhoid and paratyphoid fever are systemic infections caused by Salmonella enterica serovar Typhi or paratyphi (A, B, C). Children traveling to tropical areas are at risk to contract these diseases which can be complicated. Methods: Clinical, biological and bacteriological data were collected from 78 pediatric cases reported between 2000 and 2017 in six Parisian hospitals. Children aged 0 to 18 years old, with a diagnosis of typhoid or paratyphoid fever confirmed by bacteriological exams, were included. Epidemiologic, clinical, biological features and presence of multidrug-resistant (MDR) bacteria or intermediate susceptibility to ciprofloxacin (nalidixic acid resistant) were examined by univariate analysis and by logistic regression analysis to identify risk factors of severe typhoid in children. Results: 84,6% of the children were imported cases of typhoid fever (n=66/78) and 15,4% were autochthonous cases (n=12/78). 89,7% were caused by S.typhi (n=70/78) and 12,8% by S.paratyphi (n=10/78) including 2 co-infections. 19,2% were intrafamilial cases (n=15/78). Median age at diagnosis was 6,4 years-old [6 months-17,9 years]. 28,2% of the cases were complicated forms (n=22/78): digestive (n=8; 10,3%), neurological (n=7; 9%), pulmonary complications (n=4; 5,1%) and hemophagocytic syndrome (n=4; 5,1%). Only 5% of the children had prior immunization with typhoid non-conjugated vaccine (n=4/78). 28% of the cases (n=22/78) were caused by resistant bacteria. Thrombocytopenia and diagnosis delay was significantly associated with severe infection (p= 0.029 and p=0,01). Complicated forms were more common with MDR (p=0,1) and not statistically associated with a young age or sex in this study. Conclusions: Typhoid and paratyphoid fever are not rare in children back from tropical areas. This multicentric pediatric study seems to show that thrombocytopenia, diagnosis delay, and multidrug resistant bacteria are associated with severe typhoid fever and complicated forms in children.

Keywords: antimicrobial resistance, children, Salmonella enterica typhi and paratyphi, severe typhoid

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826 Development and Utilization of Keratin-Fibrin-Gelatin Composite Films as Potential Material for Skin Tissue Engineering Application

Authors: Sivakumar Singaravelu, Giriprasath Ramanathan, M. D. Raja, Uma Tirichurapalli Sivagnanam

Abstract:

The goal of the present study was to develop and evaluate composite film for tissue engineering application. The keratin was extracted from bovine horn and used for preparation of keratin (HK), physiologically clotted fibrin (PCF) and gelatin (G) blend films in different stoichiometric ratios (1:1:1, 1:1:2 and 1:1:3) by using solvent casting method. The composite films (HK-PCF-G) were characterized physiochemically using Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA) and Scanning Electron Microscopy (SEM). The mechanical properties of the composite films were analyzed. The results of tensile strength show that ultimate strength and elongation were 10.72 Mpa and 4.83 MPA respectively for 1:1:3 ratio combination. The SEM image showed a slight smooth surface for 1:1:3 ratio combination compared to other films. In order to impart antibacterial activities, the composite films were loaded with Mupirocin (MP) to act against infection. The composite films acted as a suitable carrier to protect and release the drug in a controlled manner. This developed composite film would be a suitable alternative material for tissue engineering application.

Keywords: bovine horn, keratin, fibrin, gelatin, tensile strength

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825 An Investigation on Hybrid Composite Drive Shaft for Automotive Industry

Authors: Gizem Arslan Özgen, Kutay Yücetürk, Metin Tanoğlu, Engin Aktaş

Abstract:

Power transmitted from the engine to the final drive where useful work is applied through a system consisting of a gearbox, clutch, drive shaft and a differential in the rear-wheel-drive automobiles. It is well-known that the steel drive shaft is usually manufactured in two pieces to increase the fundamental bending natural frequency to ensure safe operation conditions. In this work, hybrid one-piece propeller shafts composed of carbon/epoxy and glass/epoxy composites have been designed for a rear wheel drive automobile satisfying three design specifications, such as static torque transmission capability, torsional buckling and the fundamental natural bending frequency. Hybridization of carbon and glass fibers is being studied to optimize the cost/performance requirements. Composites shaft materials with various fiber orientation angles and stacking sequences are being fabricated and analyzed using finite element analysis (FEA).

Keywords: composite propeller shaft, hybridization, epoxy matrix, static torque transmission capability, torsional buckling strength, fundamental natural bending frequency.

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824 Two-Phase Flow Modelling and Numerical Simulation for Waterflooding in Enhanced Oil Recovery

Authors: Peña A. Roland R., Lozano P. Jean P.

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The waterflooding process is an enhanced oil recovery (EOR) method that appears tremendously successful. This paper shows the importance of the role of the numerical modelling of waterflooding and how to provide a better description of the fluid flow during this process. The mathematical model is based on the mass conservation equations for the oil and water phases. Rock compressibility and capillary pressure equations are coupled to the mathematical model. For discretizing and linearizing the partial differential equations, we used the Finite Volume technique and the Newton-Raphson method, respectively. The results of three scenarios for waterflooding in porous media are shown. The first scenario was estimating the water saturation in the media without rock compressibility and without capillary pressure. The second scenario was estimating the front of the water considering the rock compressibility and capillary pressure. The third case is to compare different fronts of water saturation for three fluids viscosity ratios without and with rock compressibility and without and with capillary pressure. Results of the simulation indicate that the rock compressibility and the capillary pressure produce changes in the pressure profile and saturation profile during the displacement of the oil for the water.

Keywords: capillary pressure, numerical simulation, rock compressibility, two-phase flow

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823 The Effectiveness of Communication Skills Using Transactional Analysis on the Dimensions of Marital Intimacy: An Experimental Study

Authors: Mehravar Javid, James Sexton, S. Taridashti, Joseph Dorer

Abstract:

Objective: Intimacy is among the most important factors in marital relationships and includes different aspects. Communication skills can enable couples to promote their intimacy. This experimental study was conducted to measure the effectiveness of communication skills using Transactional Analysis (TA) on various dimensions of marital intimacy. Method: The participants in this study were female teachers. Analysis of covariance was recruited in the experimental group (n =15) and control group (n =15) with pre-test and post-test. Random assignment was applied. The experimental group received the Transactional Analysis training program for 9 sessions of 2 hours each week. The instrument was the Marital Intimacy Questionnaire, with 87 items and 9 subscales. Result: The findings suggest that training in Transactional Analysis significantly increased the total score of intimacy except spiritual intimacy on the post-test. Discussion: According to the obtained data, it is concluded that communication skills using Transactional Analysis (TA) training could increase intimacy and improve marital relationships. The study highlights the differential effects on emotional, rational, sexual, and psychological intimacy compared to physical, social/recreational, and relational intimacy over a 9-week period.

Keywords: communication skills, intimacy, marital relationships, transactional analysis

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822 Impact of Meteorological Factors on Influenza Activity in Pakistan; A Tale of Two Cities

Authors: Nadia Nisar

Abstract:

Background: In the temperate regions Influenza activities occur sporadically all year round with peaks coinciding during cold months. Meteorological and environmental conditions play significant role in the transmission of influenza globally. In this study, we assessed the relationship between meteorological parameters and influenza activity in two geographical areas of Pakistan. Methods: Influenza data were collected from Islamabad (north) and Multan (south) regions of national influenza surveillance system during 2010-2015. Meteorological database was obtained from National Climatic Data Center (Pakistan). Logistic regression model with a stepwise approach was used to explore the relationship between meteorological parameters with influenza peaks. In statistical model, we used the weekly proportion of laboratory-confirmed influenza positive samples to represent Influenza activity with metrological parameters as the covariates (temperature, humidity and precipitation). We also evaluate the link between environmental conditions associated with seasonal influenza epidemics: 'cold-dry' and 'humid-rainy'. Results: We found that temperature and humidity was positively associated with influenza in north and south both locations (OR = 0.927 (0.88-0.97)) & (OR = 0.1.078 (1.027-1.132)) and (OR = 1.023 (1.008-1.037)) & (OR = 0.978 (0.964-0.992)) respectively, whilst precipitation was negatively associated with influenza (OR = 1.054 (1.039-1.070)) & (OR = 0.949 (0.935-0.963)). In both regions, temperature and humidity had the highest contribution to the model as compared to the precipitation. We revealed that the p-value for all of climate parameters is <0.05 by Independent-sample t-test. These results demonstrate that there were significant relationships between climate factors and influenza infection with correlation coefficients: 0.52-0.90. The total contribution of these three climatic variables accounted for 89.04%. The reported number of influenza cases increased sharply during the cold-dry season (i.e., winter) when humidity and temperature are at minimal levels. Conclusion: Our findings showed that measures of temperature, humidity and cold-dry season (winter) can be used as indicators to forecast influenza infections. Therefore integrating meteorological parameters for influenza forecasting in the surveillance system may benefit the public health efforts in reducing the burden of seasonal influenza. More studies are necessary to understand the role of these parameters in the viral transmission and host susceptibility process.

Keywords: influenza, climate, metrological, environmental

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821 A Theorem Related to Sample Moments and Two Types of Moment-Based Density Estimates

Authors: Serge B. Provost

Abstract:

Numerous statistical inference and modeling methodologies are based on sample moments rather than the actual observations. A result justifying the validity of this approach is introduced. More specifically, it will be established that given the first n moments of a sample of size n, one can recover the original n sample points. This implies that a sample of size n and its first associated n moments contain precisely the same amount of information. However, it is efficient to make use of a limited number of initial moments as most of the relevant distributional information is included in them. Two types of density estimation techniques that rely on such moments will be discussed. The first one expresses a density estimate as the product of a suitable base density and a polynomial adjustment whose coefficients are determined by equating the moments of the density estimate to the sample moments. The second one assumes that the derivative of the logarithm of a density function can be represented as a rational function. This gives rise to a system of linear equations involving sample moments, the density estimate is then obtained by solving a differential equation. Unlike kernel density estimation, these methodologies are ideally suited to model ‘big data’ as they only require a limited number of moments, irrespective of the sample size. What is more, they produce simple closed form expressions that are amenable to algebraic manipulations. They also turn out to be more accurate as will be shown in several illustrative examples.

Keywords: density estimation, log-density, polynomial adjustments, sample moments

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820 Nonlinear Impact Responses for a Damped Frame Supported by Nonlinear Springs with Hysteresis Using Fast FEA

Authors: T. Yamaguchi, M. Watanabe, M. Sasajima, C. Yuan, S. Maruyama, T. B. Ibrahim, H. Tomita

Abstract:

This paper deals with nonlinear vibration analysis using finite element method for frame structures consisting of elastic and viscoelastic damping layers supported by multiple nonlinear concentrated springs with hysteresis damping. The frame is supported by four nonlinear concentrated springs near the four corners. The restoring forces of the springs have cubic non-linearity and linear component of the nonlinear springs has complex quantity to represent linear hysteresis damping. The damping layer of the frame structures has complex modulus of elasticity. Further, the discretized equations in physical coordinate are transformed into the nonlinear ordinary coupled differential equations using normal coordinate corresponding to linear natural modes. Comparing shares of strain energy of the elastic frame, the damping layer and the springs, we evaluate the influences of the damping couplings on the linear and nonlinear impact responses. We also investigate influences of damping changed by stiffness of the elastic frame on the nonlinear coupling in the damped impact responses.

Keywords: dynamic response, nonlinear impact response, finite element analysis, numerical analysis

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819 Wide Dissemination of CTX-M-Type Extended-Spectrum β-Lactamases in Korean Swine Farms

Authors: Young Ah Kim, Hyunsoo Kim, Eun-Jeong Yoon, Young Hee Seo, Kyungwon Lee

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Extended-spectrum β-lactamase (ESBL)-producing Escherichia coli from food animals are considered as a reservoir for transmission of ESBL genes to human. The aim of this study is to assess the prevalence and molecular epidemiology of ESBL-producing E. coli colonization in pigs, farm workers, and farm environments to elucidate the transmission of multidrug-resistant clones from animal to human. Nineteen pig farms were enrolled across the country in Korea from August to December 2017. ESBL-producing E. coli isolates were detected in 190 pigs, 38 farm workers, and 112 sites of farm environments using ChromID ESBL (bioMerieux, Marcy l'Etoile, France), directly (stool or perirectal swab) or after enrichment (sewage). Antimicrobial susceptibility tests were done with disk diffusion methods and blaTEM, blaSHV, and blaCTX-M were detected with PCR and sequencing. The genomes of the four CTX-M-55-producing E. coli isolates from various sources in one farm were entirely sequenced to assess the relatedness of the strains. Whole genome sequencing (WGS) was performed with PacBio RS II system (Pacific Biosciences, Menlo Park, CA, USA). ESBL genotypes were 85 CTX-M-1 group (one CTX-M-3, 23 CTX-M-15, one CTX-M-28, 59 CTX-M-55, one CTX-M-69) and 60 CTX-M-9 group (41 CTX-M-14, one CTX-M-17, one CTX-M-27, 13 CTX-M-65, 4 CTX-M-102) in total 145 isolates. The rectal colonization rates were 53.2% (101/190) in pigs and 39.5% (15/38) in farm workers. In WGS, sequence types (STs) were determined as ST69 (E. coli PJFH115 isolate from a human carrier), ST457 (two E. coli isolates PJFE101 recovered from a fence and PJFA1104 from a pig) and ST5899 (E. coli PJFA173 isolate from the other pig). The four plasmids encoding CTX-M-55 (88,456 to 149, 674 base pair), whether it belonged to IncFIB or IncFIC-IncFIB type, shared IncF backbone furnishing the conjugal elements, suggesting of genes originated from same ancestor. In conclusion, the prevalence of ESBL-producing E. coli in swine farms was surprisingly high, and many of them shared common ESBL genotypes of clinical isolates such as CTX-M-14, 15, and 55 in Korea. It could spread by horizontal transfer between isolates from different reservoirs (human-animal-environment).

Keywords: Escherichia coli, extended-spectrum β-lactamase, prevalence, whole genome sequencing

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818 A Survey on Fixed Point Iterations in Modular Function Spaces and an Application to Ode

Authors: Hudson Akewe

Abstract:

This research presents complementary results with wider applications on convergence and rate of convergence of classical fixed point theory in Banach spaces to the world of the theory of fixed points of mappings defined in classes of spaces of measurable functions, known in the literature as modular function spaces. The study gives a comprehensive survey of various iterative fixed point results for the classes of multivalued ρ-contractive-like, ρ-quasi-contractive-like, ρ-quasi-contractive, ρ-Zamfirescu and ρ-contraction mappings in the framework of modular function spaces. An example is presented to demonstrate the applicability of the implicit-type iterative schemes to the system of ordinary differential equations. Furthermore, numerical examples are given to show the rate of convergence of the various explicit Kirk-type and implicit Kirk-type iterative schemes under consideration. Our results complement the results obtained on normed and metric spaces in the literature. Also, our methods of proof serve as a guide to obtain several similar improved results for nonexpansive, pseudo-contractive, and accretive type mappings.

Keywords: implicit Kirk-type iterative schemes, multivalued mappings, convergence results, fixed point

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817 Digital Material Characterization Using the Quantum Fourier Transform

Authors: Felix Givois, Nicolas R. Gauger, Matthias Kabel

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The efficient digital material characterization is of great interest to many fields of application. It consists of the following three steps. First, a 3D reconstruction of 2D scans must be performed. Then, the resulting gray-value image of the material sample is enhanced by image processing methods. Finally, partial differential equations (PDE) are solved on the segmented image, and by averaging the resulting solutions fields, effective properties like stiffness or conductivity can be computed. Due to the high resolution of current CT images, the latter is typically performed with matrix-free solvers. Among them, a solver that uses the explicit formula of the Green-Eshelby operator in Fourier space has been proposed by Moulinec and Suquet. Its algorithmic, most complex part is the Fast Fourier Transformation (FFT). In our talk, we will discuss the potential quantum advantage that can be obtained by replacing the FFT with the Quantum Fourier Transformation (QFT). We will especially show that the data transfer for noisy intermediate-scale quantum (NISQ) devices can be improved by using appropriate boundary conditions for the PDE, which also allows using semi-classical versions of the QFT. In the end, we will compare the results of the QFT-based algorithm for simple geometries with the results of the FFT-based homogenization method.

Keywords: most likelihood amplitude estimation (MLQAE), numerical homogenization, quantum Fourier transformation (QFT), NISQ devises

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816 Deciphering Tumor Stroma Interactions in Retinoblastoma

Authors: Rajeswari Raguraman, Sowmya Parameswaran, Krishnakumar Subramanian, Jagat Kanwar, Rupinder Kanwar

Abstract:

Background: Tumor microenvironment has been implicated in several cancers to regulate cell growth, invasion and metastasis culminating in outcome of therapy. Tumor stroma consists of multiple cell types that are in constant cross-talk with the tumor cells to favour a pro-tumorigenic environment. Not much is known about the existence of tumor microenvironment in the pediatric intraocular malignancy, Retinoblastoma (RB). In the present study, we aim to understand the multiple stromal cellular subtypes and tumor stromal interactions expressed in RB tumors. Materials and Methods: Immunohistochemistry for stromal cell markers CD31, CD68, alpha-smooth muscle (α-SMA), vimentin and glial fibrillary acidic protein (GFAP) was performed on formalin fixed paraffin embedded tissues sections of RB (n=12). The differential expression of stromal target molecules; fibroblast activation protein (FAP), tenascin-C (TNC), osteopontin (SPP1), bone marrow stromal antigen 2 (BST2), stromal derived factor 2 and 4 (SDF2 and SDF4) in primary RB tumors (n=20) and normal retina (n=5) was studied by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and Western blotting. The differential expression was correlated with the histopathological features of RB. The interaction between RB cell lines (Weri-Rb-1, NCC-RbC-51) and Bone marrow stromal cells (BMSC) was also studied using direct co-culture and indirect co-culture methods. The functional effect of the co-culture methods on the RB cells was evaluated by invasion and proliferation assays. Global gene expression was studied by using Affymetrix 3’ IVT microarray. Pathway prediction was performed using KEGG and the key molecules were validated using qRT-PCR. Results: The immunohistochemistry revealed the presence of several stromal cell types such as endothelial cells (CD31+;Vim+/-); macrophages (CD68+;Vim+/-); Fibroblasts (Vim+; CD31-;CD68- );myofibroblasts (α-SMA+/ Vim+) and invading retinal astrocytes/ differentiated retinal glia (GFAP+; Vim+). A characteristic distribution of these stromal cell types was observed in the tumor microenvironment, with endothelial cells predominantly seen in blood vessels and macrophages near actively proliferating tumor or necrotic areas. Retinal astrocytes and glia were predominant near the optic nerve regions in invasive tumors with sparse distribution in tumor foci. Fibroblasts were widely distributed with rare evidence of myofibroblasts in the tumor. Both gene and protein expression revealed statistically significant (P<0.05) up-regulation of FAP, TNC and BST2 in primary RB tumors compared to the normal retina. Co-culture of BMSC with RB cells promoted invasion and proliferation of RB cells in direct and indirect contact methods respectively. Direct co-culture of RB cell lines with BMSC resulted in gene expression changes in ECM-receptor interaction, focal adhesion, IL-8 and TGF-β signaling pathways associated with cancer. In contrast, various metabolic pathways such a glucose, fructose and amino acid metabolism were significantly altered under the indirect co-culture condition. Conclusion: The study suggests that the close interaction between RB cells and the stroma might be involved in RB tumor invasion and progression which is likely to be mediated by ECM-receptor interactions and secretory factors. Targeting the tumor stroma would be an attractive option for redesigning treatment strategies for RB.

Keywords: gene expression profiles, retinoblastoma, stromal cells, tumor microenvironment

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815 Cold Crystallization of Poly (Ether Ether Ketone)/Graphene Composites by Time-Resolved Synchrotron X-Ray Diffraction

Authors: A. Alvaredo , R. Guzman De Villoria, P. Castell, Juan P. Fernandez-Blazquez

Abstract:

Since graphene was discovered in 2004, has been considered as superb material, due to its outstanding mechanical, electrical and thermal properties. Graphene has been incorporated as reinforcement in several high performance polymers in order to obtain a good balance of properties and to get new properties as thermal or electric conductivity. As well known, the properties of semicrystalline polymer and its composites depends heavily on degree of crystallinity. In this context, our research group has studied the crystallization behavior from amorphous state of PEEK/GNP composites. The monitoring of cold crystallization processes studied by time-resolved simultaneous wide-angle X-ray scattering (WAXS) and small-angle X-ray scattering (SAXS). These techniques allowed to get an extremely relevant information about the evolution of the morphology of the PEEK/GNP composites. In addition, the thermal evolution of cold crystallization was followed by differential scanning calorimetry (DSC) as well. The experimental results showed changes in crystallization kinetics and c parameter unit cell when adding graphene. The main aim of this work is to produce PEEK/GNP composites and characterize their morphology, unit cell parameters and crystallization kinetic.

Keywords: PEEK, graphene, synchrotron, cold crystallization

Procedia PDF Downloads 342
814 Antimicrobial Effects and Phytochemical Analysis of Chrysophyllum Albidum Plant Parts (Leaves, Roots and Seeds) Extracts on Bacterial Isolates from Urinary Catheters

Authors: Ebere Christian Ugochukwu, Okafor Josephine, Oyawoye Tomisin

Abstract:

The occurrence of multidrug resistance patterns that have been developed by bacteria has made it difficult to properly treat infections using standard clinical medications. Hence, the use of herbs as an alternative source of therapy is considered cheap and easily accessible to locals. This research explored the antimicrobial effects of aqueous and ethanolic extracts obtained from Chrysophyllum albidum (commonly called ‘Agbalumo’ in southwest Nigeria and ‘Udara’ in the eastern and southern parts of Nigeria) plant parts (leaves, roots and seeds) against bacteria isolated from urinary catheter tips. The following isolates were obtained; Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Proteus mirabilis, and Klebsiella aerogenes. The agar well diffusion method was used. The average percentages of antimicrobial resistance of the isolates to gentamycin were 45.5% for P. aeruginosa, 42.1% for E. coli, 46.9% for K. aerogenes, and ˃90% for other isolates. Qualitative phytochemical screening of the plant parts extracts was done using chemical test for the screening and identification of bioactive chemical constituents. The ethanolic extract mixtures (leaf, root and seed) had the greatest effect on all the isolates, with inhibition zones (IZs) ranging from 8-26 mm and MICs ranging from <16-32 mg/ml. The Potencies of the C. albidum extracts based on the IZ and MIC values were greater in the extract mixtures, followed by those in the roots. Phytochemical screening revealed that all the extracts contained phenol except for the seeds while tannins were present in all the extracts except the leaves. The activity of the ethanolic extracts of each part at high and low concentrations was greater than that of the aqueous extracts at the same concentrations (p<0.05). The acute toxicity results showed that the LD50 of the extracts was ˃5000 mg/body weight, indicating no toxicity. The antibacterial activities of the extract mixtures and roots on the isolates confirmed the use of C. albidum in folk medicine for the treatment of CAUTIs, hence indicating its antibacterial potential for use in novel antibiotic production.

Keywords: antimicrobials, susceptibility, minimum inhibitory concentration, extracts

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813 Paraffin/Expanded Perlite Composite as a Novel Form-Stable Phase Change Material for Latent Heat Energy Storage

Authors: Awni Alkhazaleh

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Latent heat storage using Phase Change Materials (PCMs) has attracted growing attention recently in the renewable energy utilization and building energy efficiency. Paraffin (PA) of low melting temperature, which is close to human comfort temperature in the range of 24-28 °C has been considered to be used in building applications. A form-stable composite Paraffin/Expanded perlite (PA-EP) has been prepared by retaining PA into porous particles of EP. DSC (Differential scanning calorimeter) is used to measure the thermal properties of PA in the form-stable composite with/without building materials. TGA (Thermal gravimetric analysis) shows that the composite is thermally stable. SEM (Scanning electron microscope) demonstrates that the layer structure of the EP particles is uniformly absorbed by PA. The mechanical properties in flexural mode have been discussed. The thermal energy storage performance has been evaluated using a small test room (100 mm ×100 mm ×100 mm) with thickness 10 mm. The flammability test of modified sample has been discussed using a cone calorimeter. The results confirm that the form-stable composite PA has the function of reducing building energy consumption.

Keywords: flammability, latent heat storage, paraffin, plasterboard

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812 Visual and Chemical Servoing of a Hexapod Robot in a Confined Environment Using Jacobian Estimator

Authors: Guillaume Morin-Duponchelle, Ahmed Nait Chabane, Benoit Zerr, Pierre Schoesetters

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Industrial inspection can be achieved through robotic systems, allowing visual and chemical servoing. A popular scheme for visual servo-controlled robotic is the image-based servoing sys-tems. In this paper, an approach of visual and chemical servoing of a hexapod robot using a visual and chemical Jacobian matrix are proposed. The basic idea behind the visual Jacobian matrix is modeling the differential relationship between the camera system and the robotic control system to detect and track accurately points of interest in confined environments. This approach allows the robot to easily detect and navigates to the QR code or seeks a gas source localization using surge cast algorithm. To track the QR code target, a visual servoing based on Jacobian matrix is used. For chemical servoing, three gas sensors are embedded on the hexapod. A Jacobian matrix applied to the gas concentration measurements allows estimating the direction of the main gas source. The effectiveness of the proposed scheme is first demonstrated on simulation. Finally, a hexapod prototype is designed and built and the experimental validation of the approach is presented and discussed.

Keywords: chemical servoing, hexapod robot, Jacobian matrix, visual servoing, navigation

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811 Physicochemical Attributes of Pectin Hydrogel and Its Wound Healing Activity

Authors: Nor Khaizan Anuar, Nur Karimah Aziz, Tin Wui Wong, Ahmad Sazali Hamzah, Wan Rozita Wan Engah

Abstract:

The physicochemical attributes and wound healing activity of pectin hydrogel in rat models, following partial thickness thermal injury were investigated. The pectin hydrogel was prepared by solvent evaporation method with the aid of glutaraldehyde as crosslinking agent and glycerol as plasticizer. The physicochemical properties were mainly evaluated using differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy, while the wound healing activity was examined by the macroscopic images, wound size reduction and histological evaluation using haematoxylin and eosin (H&E) stain for 14 days. The DSC and FTIR analysis suggested that pectin hydrogel exhibited higher extent of polymer-polymer interaction at O-H functional group in comparison to the unprocessed pectin. This was indicated by the increase of endothermic enthalpy values from 139.35 ± 13.06 J/g of unprocessed pectin to 156.23 ± 2.86 J/g of pectin hydrogel, as well as the decrease of FTIR wavenumber corresponding to O-H at 3432.07 ± 0.49 cm-1 of unprocessed pectin to 3412.62 ± 13.06 cm-1 of pectin hydrogel. Rats treated with pectin hydrogel had significantly smaller wound size (Student’s t-test, p<0.05) when compared to the untreated group starting from day 7 until day 14. H&E staining indicated that wounds received pectin hydrogel had more fibroblasts, blood vessels and collagen bundles on day 14 in comparison to the untreated rats.

Keywords: pectin, physicochemical, rats, wound

Procedia PDF Downloads 354
810 An Optimal Control Model to Determine Body Forces of Stokes Flow

Authors: Yuanhao Gao, Pin Lin, Kees Weijer

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In this paper, we will determine the external body force distribution with analysis of stokes fluid motion using mathematical modelling and numerical approaching. The body force distribution is regarded as the unknown variable and could be determined by the idea of optimal control theory. The Stokes flow motion and its velocity are generated by given forces in a unit square domain. A regularized objective functional is built to match the numerical result of flow velocity with the generated velocity data. So that the force distribution could be determined by minimizing the value of objective functional, which is also the difference between the numerical and experimental velocity. Then after utilizing the Lagrange multiplier method, some partial differential equations are formulated consisting the optimal control system to solve. Finite element method and conjugate gradient method are used to discretize equations and deduce the iterative expression of target body force to compute the velocity numerically and body force distribution. Programming environment FreeFEM++ supports the implementation of this model.

Keywords: optimal control model, Stokes equation, finite element method, conjugate gradient method

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809 Case Report: A Case of Confusion with Review of Sedative-Hypnotic Alprazolam Use

Authors: Agnes Simone

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A 52-year-old male with unknown psychiatric and medical history was brought to the Psychiatric Emergency Room by ambulance directly from jail. He had been detained for three weeks for possession of a firearm while intoxicated. On initial evaluation, the patient was unable to provide a reliable history. He presented with odd jerking movements of his extremities and catatonic features, including mutism and stupor. His vital signs were stable. Patient was transferred to the medical emergency department for work-up of altered mental status. Due to suspicion for opioid overdose, the patient was given naloxone (Narcan) with no improvement. Laboratory work-up included complete blood count, comprehensive metabolic panel, thyroid stimulating hormone, vitamin B12, folate, magnesium, rapid plasma reagin, HIV, blood alcohol level, aspirin, and Tylenol blood levels, urine drug screen, and urinalysis, which were all negative. CT head and chest X-Ray were also negative. With this negative work-up, the medical team concluded there was no organic etiology and requested inpatient psychiatric admission. Upon re-evaluation by psychiatry, it was evident that the patient continued to have an altered mental status. Of note, the medical team did not include substance withdrawal in the differential diagnosis due to stable vital signs and a negative urine drug screen. The psychiatry team decided to check California's prescription drug monitoring program (CURES) and discovered that the patient was prescribed benzodiazepine alprazolam (Xanax) 2mg BID, a sedative-hypnotic, and hydrocodone/acetaminophen 10mg/325mg (Norco) QID, an opioid. After a thorough chart review, his daughter's contact information was found, and she confirmed his benzodiazepine and opioid use, with recent escalation and misuse. It was determined that the patient was experiencing alprazolam withdrawal, given this collateral information, his current symptoms, negative urine drug screen, and recent abrupt discontinuation of medications while incarcerated. After admission to the medical unit and two doses of alprazolam 2mg, the patient's mental status, alertness, and orientation improved, but he had no memory of the events that led to his hospitalization. He was discharged with a limited supply of alprazolam and a close follow-up to arrange a taper. Accompanying this case report, a qualitative review of presentations with alprazolam withdrawal was completed. This case and the review highlights: (1) Alprazolam withdrawal can occur at low doses and within just one week of use. (2) Alprazolam withdrawal can present without any vital sign instability. (3) Alprazolam withdrawal does not respond to short-acting benzodiazepines but does respond to certain long-acting benzodiazepines due to its unique chemical structure. (4) Alprazolam withdrawal is distinct from and more severe than other benzodiazepine withdrawals. This case highlights (1) the importance of physician utilization of drug-monitoring programs. This case, in particular, relied on California's drug monitoring program. (2) The importance of obtaining collateral information, especially in cases in which the patient is unable to provide a reliable history. (3) The importance of including substance intoxication and withdrawal in the differential diagnosis even when there is a negative urine drug screen. Toxidrome of withdrawal can be delayed. (4) The importance of discussing addiction and withdrawal risks of medications with patients.

Keywords: addiction risk of benzodiazepines, alprazolam withdrawal, altered mental status, benzodiazepines, drug monitoring programs, sedative-hypnotics, substance use disorder

Procedia PDF Downloads 126
808 A Stochastic Volatility Model for Optimal Market-Making

Authors: Zubier Arfan, Paul Johnson

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The electronification of financial markets and the rise of algorithmic trading has sparked a lot of interest from the mathematical community, for the market making-problem in particular. The research presented in this short paper solves the classic stochastic control problem in order to derive the strategy for a market-maker. It also shows how to calibrate and simulate the strategy with real limit order book data for back-testing. The ambiguity of limit-order priority in back-testing is dealt with by considering optimistic and pessimistic priority scenarios. The model, although it does outperform a naive strategy, assumes constant volatility, therefore, is not best suited to the LOB data. The Heston model is introduced to describe the price and variance process of the asset. The Trader's constant absolute risk aversion utility function is optimised by numerically solving a 3-dimensional Hamilton-Jacobi-Bellman partial differential equation to find the optimal limit order quotes. The results show that the stochastic volatility market-making model is more suitable for a risk-averse trader and is also less sensitive to calibration error than the constant volatility model.

Keywords: market-making, market-microsctrucure, stochastic volatility, quantitative trading

Procedia PDF Downloads 141
807 How to Break an Outbreak: Containment Measures of a Salmonella Outbreak Associated with Egg Consumption

Authors: Gal Zagron, Nitza Abramson, Deena R. Zimmerman, Chen Stein-Zamir

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Background: Salmonella enteritidis is a common cause of foodborne outbreaks, primarily associated with poultry eggs. S. enteritidis This is the only Salmonella type that is found inside the eggshell. A rise in Salmonella enteritidis notifications was noted in spring 2017. Aims: The aim of this study is to describe the epidemiological investigation of the outbreak in the Jerusalem district, along with the containment measures taken. Methods: This study is a population-based epidemiological study with a description of environmental control activities. Results: During the months May - July, 2017 848 salmonellosis cases were reported to the Jerusalem district health office compared to 294 cases May - July 2016. Salmonella enteritidis was isolated in 58% of reported cases. Clusters and outbreaks ( > 2 cases) were reported among nursery schools, nursing homes, persons residing in one kibbutz and several cases in different food service establishments in the Jerusalem district. Epidemiological investigations revealed eggs consumption as a common feature among the cases (uncooked or undercooked eggs in most cases). A national investigation among egg suppliers revealed that most cases consumed eggs provided by a single provider with isolation of Salmonella enteritidis at the source as well. Containment measures were taken to control the epidemic including distributing information via electronic and written media to the public, searching for all egg distribution centers, informing local authorities, the poultry council and food stores. The eggs originating from the provider were recalled and extinguished. Written instructions to all food preparation facilities in the district were distributed regarding the proper storage and preparation of eggs. The number of reported cases declined and the outbreak vanished during correlating months of 2018. Conclusions: The investigation of Salmonella enteritidis outbreaks should include epidemiological and laboratory investigations, tracing the source of the eggs and testing the eggs and the source of eggs. Health education activities are essential as to the proper handling of eggs and egg products aiming to minimize susceptibility to Salmonella infection.

Keywords: epidemiological investigation, food-borne disease, food safety, Salmonella enteritidis

Procedia PDF Downloads 135
806 Suitability of Wood Sawdust Waste Reinforced Polymer Composite for Fireproof Doors

Authors: Timine Suoware, Sylvester Edelugo, Charles Amgbari

Abstract:

The susceptibility of natural fibre polymer composites to flame has necessitated research to improve and develop flame retardant (FR) to delay the escape of combustible volatiles. Previous approaches relied mostly on FR such as aluminium tri-hydroxide (ATH) and ammonium polyphosphate (APP) to improve fire performances of wood sawdust polymer composites (WSPC) with emphasis on non-structural building applications. In this paper, APP was modified with gum Arabic powder (GAP) and then hybridized with ATH at 0, 12 and 18% loading ratio to form new FR species; WSPC12%APP-GAP and WSPC18%ATH/APP-GAP. The FR species were incorporated in wood sawdust waste reinforced in polyester resin to form panels for fireproof doors. The panels were produced using hand lay compression moulding technique and cured at room temperature. Specimen cut from panels were then tested for tensile strength (TS), flexural strength (FS) and impact strength (IS) using universal testing machine and impact tester; thermal stability using (TGA/DSC 1: Metler Toledo); time-to-ignition (Tig), heat release rates (HRR); peak HRR (HRRp), average HRR (HRRavg), total HRR (THR), peak mass loss rate (MLRp), average smoke production rate (SPRavg) and carbon monoxide production (COP ) were obtained using the cone calorimeter apparatus. From the mechanical properties obtained, improvements of IS for the panels were not noticeable whereas TS and FS for WSPC12%APP-GAP respectively stood at 12.44 MPa and 85.58 MPa more than those without FR (WSPC0%). For WSC18%ATH/APP-GAP TS and FS respectively stood at 16.45 MPa and 50.49 MPa more compared to (WSPC0%). From the thermal analysis, the panels did not exhibit any significant change as early degradation was observed. At 900 OC, the char residues improved by 15% for WSPC12%APP-GAP and 19% for WSPC18%ATH/APP-GAP more than (WSC0%) at 5%, confirming the APP-GAP to be a good FR. At 50 kW/m2 heat flux (HF), WSPC12%APP-GAP improved better the fire behaviour of the panels when compared to WSC0% as follows; Tig = 46 s, HRRp = 56.1 kW/2, HRRavg = 32.8 kW/m2, THR = 66.6 MJ/m2, MLRp = 0.103 g/s, TSR = 0.04 m2/s and COP = 0.051 kg/kg. These were respectively more than WSC0%. It can be concluded that the new concept of modifying FR with GAP in WSC could meet the requirement of a fireproof door for building applications.

Keywords: composite, flame retardant, wood sawdust, fireproof doors

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805 Unsteady Heat and Mass Transfer in MHD Flow of Nanofluids over Stretching Sheet with a Non Uniform Heat Source/Sink

Authors: Bandari Shankar, Yohannes Yirga

Abstract:

In this paper, the problem of heat and mass transfer in unsteady MHD boundary-layer flow of nanofluids over stretching sheet with a non uniform heat source/sink is considered. The unsteadiness in the flow and temperature is caused by the time-dependent stretching velocity and surface temperature. The unsteady boundary layer equations are transformed to a system of non-linear ordinary differential equations and solved numerically using Keller box method. The velocity, temperature, and concentration profiles were obtained and utilized to compute the skin-friction coefficient, local Nusselt number, and local Sherwood number for different values of the governing parameters viz. solid volume fraction parameter, unsteadiness parameter, magnetic field parameter, Schmidt number, space-dependent and temperature-dependent parameters for heat source/sink. A comparison of the numerical results of the present study with previously published data revealed an excellent agreement

Keywords: unsteady, heat and mass transfer, manetohydrodynamics, nanofluid, non-uniform heat source/sink, stretching sheet

Procedia PDF Downloads 263
804 Association of 105A/C IL-18 Gene Single Nucleotide Polymorphism with House Dust Mite Allergy in an Atopic Filipino Population

Authors: Eisha Vienna M. Fernandez, Cristan Q. Cabanilla, Hiyasmin Lim, John Donnie A. Ramos

Abstract:

Allergy is a multifactorial disease affecting a significant proportion of the population. It is developed through the interaction of allergens and the presence of certain polymorphisms in various susceptibility genes. In this study, the correlation of the 105A/C single nucleotide polymorphism (SNP) of the IL-18 gene and house dust mite-specific IgE among Filipino allergic and non-allergic population was investigated. Atopic status was defined by serum total IgE concentration of ≥100 IU/mL, while house dust mite allergy was defined by specific IgE value ≥ +1SD of IgE of nonatopic participants. Two hundred twenty match-paired Filipino cases and controls aged 6-60 were the subjects of this investigation. The level of total IgE and Specific IgE were measured using Enzyme-Linked Immunosorbent Assay (ELISA) while Polymerase Chain Reaction – Restriction Fragment Length Polymorphism (PCR-RFLP) analysis was used in the SNP detection. Sensitization profiles of the allergic patients revealed that 97.3% were sensitized to Blomia tropicalis, 40.0% to Dermatophagoides farinae, and 29.1% to Dermatophagoides pteronyssinus. Multiple sensitization to HDMs was also observed among the 47.27% of the atopic participants. Any of the allergy classes of the atopic triad were exhibited by the cases (allergic asthma: 48.18%; allergic rhinitis: 62.73%; atopic dermatitis: 19.09%), and two or all of these atopic states are concurrently occurring in 26.36% of the cases. A greater proportion of the atopic participants with allergic asthma and allergic rhinitis were sensitized to D. farinae, and D. pteronyssinus, while more of those with atopic dermatitis were sensitized to D. pteronyssinus than D. farinae. Results show that there is overrepresentation of the allele “A” of the 105A/C IL-18 gene SNP in both cases and control groups of the population. The genotype that predominate the population is the heterozygous “AC”, followed by the homozygous wild “AA”, and the homozygous variant “CC” being the least. The study confirmed a positive association between serum specific IgE against B. tropicalis and D. pteronyssinus and the allele “C” (Bt P=0.021, Dp P=0.027) and “AC” (Bt P=0.003, Dp P=0.026) genotype. Findings also revealed that the genotypes “AA” (OR:1.217; 95% CI: 0.701-2.113) and “CC” (OR, 3.5; 95% CI: 0.727-16.849) increase the risk of developing allergy. This indicates that the 105A/C IL-18 gene SNP is a candidate genetic marker for HDM allergy among Filipino patients.

Keywords: house dust mite allergy, interleukin-18 (IL-18), single nucleotide polymorphism,

Procedia PDF Downloads 455