Search results for: full genome sequencing
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3047

Search results for: full genome sequencing

2627 Design and Optimization of a Customized External Fixation Device for Lower Limb Injuries

Authors: Mohammed S. Alqahtani, Paulo J. Bartolo

Abstract:

External fixation is a common technique for the treatment and stabilization of bone fractures. Different designs have been proposed by companies and research groups, but all of them present limitations such as high weight, not comfortable to use, and not customized to individual patients. This paper proposes a lightweight customized external fixator, overcoming some of these limitations. External fixators are designed using a set of techniques such as medical imaging, CAD modelling, finite element analysis, and full factorial design of experiments. Key design parameters are discussed, and the optimal set of parameters is used to design the final external fixator. Numerical simulations are used to validate design concepts. Results present an optimal external fixation design with weight reduction of 13% without compromising its stiffness and structural integrity. External fixators are also designed to be additively manufactured, allowing to develop a strategy for personalization.

Keywords: computer-aided design modelling, external fixation, finite element analysis, full factorial, personalization

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2626 Computer Based Identification of Possible Molecular Targets for Induction of Drug Resistance Reversion in Multidrug Resistant Mycobacterium Tuberculosis

Authors: Oleg Reva, Ilya Korotetskiy, Marina Lankina, Murat Kulmanov, Aleksandr Ilin

Abstract:

Molecular docking approaches are widely used for design of new antibiotics and modeling of antibacterial activities of numerous ligands which bind specifically to active centers of indispensable enzymes and/or key signaling proteins of pathogens. Widespread drug resistance among pathogenic microorganisms calls for development of new antibiotics specifically targeting important metabolic and information pathways. A generally recognized problem is that almost all molecular targets have been identified already and it is getting more and more difficult to design innovative antibacterial compounds to combat the drug resistance. A promising way to overcome the drug resistance problem is an induction of reversion of drug resistance by supplementary medicines to improve the efficacy of the conventional antibiotics. In contrast to well established computer-based drug design, modeling of drug resistance reversion still is in its infancy. In this work, we proposed an approach to identification of compensatory genetic variants reducing the fitness cost associated with the acquisition of drug resistance by pathogenic bacteria. The approach was based on an analysis of the population genetic of Mycobacterium tuberculosis and on results of experimental modeling of the drug resistance reversion induced by a new anti-tuberculosis drug FS-1. The latter drug is an iodine-containing nanomolecular complex that passed clinical trials and was admitted as a new medicine against MDR-TB in Kazakhstan. Isolates of M. tuberculosis obtained on different stages of the clinical trials and also from laboratory animals infected with MDR-TB strain were characterized by antibiotic resistance, and their genomes were sequenced by the paired-end Illumina HiSeq 2000 technology. A steady increase in sensitivity to conventional anti-tuberculosis antibiotics in series of isolated treated with FS-1 was registered despite the fact that the canonical drug resistance mutations identified in the genomes of these isolates remained intact. It was hypothesized that the drug resistance phenotype in M. tuberculosis requires an adjustment of activities of many genes to compensate the fitness cost of the drug resistance mutations. FS-1 cased an aggravation of the fitness cost and removal of the drug-resistant variants of M. tuberculosis from the population. This process caused a significant increase in genetic heterogeneity of the Mtb population that was not observed in the positive and negative controls (infected laboratory animals left untreated and treated solely with the antibiotics). A large-scale search for linkage disequilibrium associations between the drug resistance mutations and genetic variants in other genomic loci allowed identification of target proteins, which could be influenced by supplementary drugs to increase the fitness cost of the drug resistance and deprive the drug-resistant bacterial variants of their competitiveness in the population. The approach will be used to improve the efficacy of FS-1 and also for computer-based design of new drugs to combat drug-resistant infections.

Keywords: complete genome sequencing, computational modeling, drug resistance reversion, Mycobacterium tuberculosis

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2625 Atmospheric Full Scale Testing of a Morphing Trailing Edge Flap System for Wind Turbine Blades

Authors: Thanasis K. Barlas, Helge A. Madsen

Abstract:

A novel Active Flap System (AFS) has been developed at DTU Wind Energy, as a result of a 3-year R\&D project following almost 10 years of innovative research in this field. The full-scale AFS comprises an active deformable trailing edge has been tested at the unique rotating test facility at the Risoe Campus of DTU Wind Energy in Denmark. The design and instrumentation of the wing section and the active flap system (AFS) are described. The general description and objectives of the rotating test rig at the Risoe campus of DTU are presented, as used for the aeroelastic testing of the AFS in the recently finalized INDUFLAP project. The general description and objectives are presented, along with an overview of sensors on the setup and the test cases. The post-processing of data is discussed and results of steady flap step and azimuth control flap cases are presented.

Keywords: morphing, adaptive, flap, smart blade, wind turbine

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2624 Numerical Crashworthiness Investigations of a Full-Scale Composite Fuselage Section

Authors: Redouane Lombarkia

Abstract:

To apply a new material model developed and validated for plain weave fabric CFRP composites usually used in stanchions in sub-cargo section in aircrafts. This work deals with the development of a numerical model of the fuselage section of commercial aircraft based on the pure explicit finite element method FEM within Abaqus/Explicit commercial code. The aim of this work is the evaluation of the energy absorption capabilities of a full-scale composite fuselage section, including sub-cargo stanchions, Drop tests were carried out from a free fall height of about 5 m and impact velocity of about 6 m∕s. To asses, the prediction efficiency of the proposed numerical modeling procedure, a comparison with literature existed experimental results was performed. We demonstrate the efficiency of the proposed methodology to well capture crash damage mechanisms compared to experimental results

Keywords: crashworthiness, fuselage section, finite elements method (FEM), stanchions, specific energy absorption SEA

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2623 Improved Water Productivity by Deficit Irrigation: Implications for Water Saving in Orange, Olive and Vineyard Orchards in Arid Conditions of Tunisia

Authors: K. Nagaz, F. El Mokh, M. Masmoudi, N. Ben Mechlia, M. O. Baba Sy, G. Ghiglieri

Abstract:

Field experiments on deficit irrigation (DI) were performed in Médenine, Tunisia on drip-irrigated olive, orange and grapevine orchards during 2013 and 2014. Four irrigation treatments were compared: full irrigation (FI), which was irrigated at 100% of ETc for the whole season; two deficit irrigation (DI) strategies -DI75 and DI50- which received, respectively, 25 and 50% less water than FI; and traditional farming management (FM) - with water input much less than actually needed. The traditional farming (FM) applied 11, 18, 30 and 33% less water than the FI treatment, respectively, in orange, grapevine and table and oil olive orchards, indicating that the farmers practices represent a form of unintended deficit irrigation. Yield was reduced when deficit irrigation was applied and there were significant differences between DI75, DI50 and FM treatments. Significant differences were not observed between DI50 and FM treatments even though numerically smaller yield was observed in the former (DI50) as compared to the latter (FM). The irrigation water productivity (IWP) was significantly affected by irrigation treatments. The smallest IWP was recorded under the FI treatment, while the largest IWP was obtained under the deficit irrigation treatment (DI50). The DI50 and FM treatments reduced the economic return compared to the full treatment (FI), while the DI75 treatment resulted in a better economic return in respect to DI50 and FM. Full irrigation (FI) could be recommended for olive, orange and grapevine irrigation under the arid climate of Tunisia. Nevertheless, the treatment DI75 can be applied as a strategy under water scarcity conditions in commercial olive, orange and grapevine orchards allowing water savings up to 25% but with some reduction in yield and net return. The results would be helpful in adopting deficit irrigation in ways that enhance net financial returns.

Keywords: water productivity, deficit irrigation, drip irrigation, orchards

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2622 CRISPR/Cas9 Based Gene Stacking in Plants for Virus Resistance Using Site-Specific Recombinases

Authors: Sabin Aslam, Sultan Habibullah Khan, James G. Thomson, Abhaya M. Dandekar

Abstract:

Losses due to viral diseases are posing a serious threat to crop production. A quick breakdown of resistance to viruses like Cotton Leaf Curl Virus (CLCuV) demands the application of a proficient technology to engineer durable resistance. Gene stacking has recently emerged as a potential approach for integrating multiple genes in crop plants. In the present study, recombinase technology has been used for site-specific gene stacking. A target vector (pG-Rec) was designed for engineering a predetermined specific site in the plant genome whereby genes can be stacked repeatedly. Using Agrobacterium-mediated transformation, the pG-Rec was transformed into Coker-312 along with Nicotiana tabacum L. cv. Xanthi and Nicotiana benthamiana. The transgene analysis of target lines was conducted through junction PCR. The transgene positive target lines were used for further transformations to site-specifically stack two genes of interest using Bxb1 and PhiC31 recombinases. In the first instance, Cas9 driven by multiplex gRNAs (for Rep gene of CLCuV) was site-specifically integrated into the target lines and determined by the junction PCR and real-time PCR. The resulting plants were subsequently used to stack the second gene of interest (AVP3 gene from Arabidopsis for enhancing cotton plant growth). The addition of the genes is simultaneously achieved with the removal of marker genes for recycling with the next round of gene stacking. Consequently, transgenic marker-free plants were produced with two genes stacked at the specific site. These transgenic plants can be potential germplasm to introduce resistance against various strains of cotton leaf curl virus (CLCuV) and abiotic stresses. The results of the research demonstrate gene stacking in crop plants, a technology that can be used to introduce multiple genes sequentially at predefined genomic sites. The current climate change scenario highlights the use of such technologies so that gigantic environmental issues can be tackled by several traits in a single step. After evaluating virus resistance in the resulting plants, the lines can be a primer to initiate stacking of further genes in Cotton for other traits as well as molecular breeding with elite cotton lines.

Keywords: cotton, CRISPR/Cas9, gene stacking, genome editing, recombinases

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2621 The Effect of Whole-Body Vertical Rhythm Training on Fatigue, Physical Activity, and Quality of Life to the Middle-Aged and Elderly with Hemodialysis Patients

Authors: Yen-Fen Shen, Meng-Fan Li

Abstract:

The study aims to investigate the effect of full-body vertical rhythmic training on fatigue, physical activity, and quality of life among middle-aged and elderly hemodialysis patients. The study adopted a quasi-experimental research method and recruited 43 long-term hemodialysis patients from a medical center in northern Taiwan, with 23 and 20 participants in the experimental and control groups, respectively. The experimental group received full-body vertical rhythmic training as an intervention, while the control group received standard hemodialysis care without any intervention. Both groups completed the measurements by using "Fatigue Scale", "Physical Activity Scale" and "Chinese version of the Kidney Disease Quality of Life Questionnaire" before and after the study. The experimental group underwent a 10-minute full-body vertical rhythmic training three times per week, which lasted for eight weeks before receiving regular hemodialysis treatment. The data were analyzed by SPSS 25 software, including descriptive statistics such as frequency distribution, percentages, means, and standard deviations, as well as inferential statistics, including chi-square, independent samples t-test, and paired samples t-test. The study results are summarized as follows: 1. There were no significant differences in demographic variables, fatigue, physical activity, and quality of life between the experimental and control groups in the pre-test. 2. After the intervention of the “full-body vertical rhythmic training,” the experimental group showed significantly better results in the category of "feeling tired and fatigued in the lower back", "physical functioning role limitation", "bodily pain", "social functioning", "mental health", and "impact of kidney disease on life quality." 3. The paired samples t-test results revealed that the control group experienced significant differences between the pre-test and post-test in the categories of feeling tired and fatigued in the lower back, bodily pain, social functioning mental health, and impact of kidney disease on life quality, with scores indicating a decline in life quality. Conversely, the experimental group only showed a significant worsening in bodily pain" and the impact of kidney disease on life quality, with lower change values compared to the control group. Additionally, there was an improvement in the condition of "feeling tired and fatigued in the lower back" for the experimental group. Conclusion: The intervention of the “full-body vertical rhythmic training” had a certain positive effect on the quality of life of the experimental group. While it may not entirely enhance patients' quality of life, it can mitigate the negative impact of kidney disease on certain aspects of the body. The study provides clinical practice, nursing education, and research recommendations based on the results and discusses the limitations of the research.

Keywords: hemodialysis, full-body vertical rhythmic training, fatigue, physical activity, quality of life

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2620 Deficit Drip Irrigation in Organic Cultivation of Aromatic Plant

Authors: Vasileios A. Giouvanis, Christos D. Papanikolaou, Dimitrios S. Dimakas, Maria A. Sakellariou-Makrantonaki

Abstract:

In countries with limited water resources, where the irrigation demands are higher than the 70% of the total water use, the demand for fresh water increases while the quality of this natural resource is downgraded. The aromatic and pharmaceutical plants hold a high position in the culture of the most civilizations through the centuries. The ‘Mountain Tea,’ species of the Greek flora, is part of a series of aromatic plants and herbs that are famous for their pharmaceutical properties as well as their byproducts and their essential oils. The aim of this research was to study the effects of full and deficit irrigation on the growing and productive characteristics of organically cultivated ‘Mountain Tea’ (Sideritis raeseri). The research took place at the University of Thessaly farm in Velestino, Magnesia - Central Greece, during the year 2017, which was the third growing season. The experiment consisted of three treatments in three replications. The experimental design was a fully randomized complete block. Surface drip irrigation was used to irrigate the experimental plots. In the first treatment, the 75% (deficit irrigation) of the daily water needs was applied. In the second treatment, the 100% (full irrigation) of the daily water needs was applied. The third treatment was not irrigated (rainfed). The crop water needs were calculated according to the daily measured evapotranspiration (ETc) using the Penman-Monteith method (FAO 56). The plants’ height, fresh and dry biomass production were measured. The results showed that only the irrigated ‘Mountain Tea’ can be cultivated at low altitude areas with satisfactory results. Moreover, there are no statistically significant differences (P < 0.05) at the growing and productive characteristics between full and deficit irrigation treatments, which proves that by deficit irrigation, an important amount of irrigation water can be saved.

Keywords: mountain tea, surface drip irrigation, deficit irrigation, water saving

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2619 Investigating the Efficiency of Granular Sludge for Recovery of Phosphate from Wastewater

Authors: Sara Salehi, Ka Yu Cheng, Anna Heitz, Maneesha Ginige

Abstract:

This study investigated the efficiency of granular sludge for phosphorous (P) recovery from wastewater. A laboratory scale sequencing batch reactor (SBR) was operated under alternating aerobic/anaerobic conditions to enrich a P accumulating granular biomass. This study showed that an overall 45-fold increase in P concentration could be achieved by reducing the volume of the P capturing liquor by 5-fold in the anaerobic P release phase. Moreover, different fractions of the granular biomass have different individual contributions towards generating a concentrated stream of P.

Keywords: granular sludge, PAOs, P recovery, SBR

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2618 User Guidance for Effective Query Interpretation in Natural Language Interfaces to Ontologies

Authors: Aliyu Isah Agaie, Masrah Azrifah Azmi Murad, Nurfadhlina Mohd Sharef, Aida Mustapha

Abstract:

Natural Language Interfaces typically support a restricted language and also have scopes and limitations that naïve users are unaware of, resulting in errors when the users attempt to retrieve information from ontologies. To overcome this challenge, an auto-suggest feature is introduced into the querying process where users are guided through the querying process using interactive query construction system. Guiding users to formulate their queries, while providing them with an unconstrained (or almost unconstrained) way to query the ontology results in better interpretation of the query and ultimately lead to an effective search. The approach described in this paper is unobtrusive and subtly guides the users, so that they have a choice of either selecting from the suggestion list or typing in full. The user is not coerced into accepting system suggestions and can express himself using fragments or full sentences.

Keywords: auto-suggest, expressiveness, habitability, natural language interface, query interpretation, user guidance

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2617 Validation of Asymptotic Techniques to Predict Bistatic Radar Cross Section

Authors: M. Pienaar, J. W. Odendaal, J. C. Smit, J. Joubert

Abstract:

Simulations are commonly used to predict the bistatic radar cross section (RCS) of military targets since characterization measurements can be expensive and time consuming. It is thus important to accurately predict the bistatic RCS of targets. Computational electromagnetic (CEM) methods can be used for bistatic RCS prediction. CEM methods are divided into full-wave and asymptotic methods. Full-wave methods are numerical approximations to the exact solution of Maxwell’s equations. These methods are very accurate but are computationally very intensive and time consuming. Asymptotic techniques make simplifying assumptions in solving Maxwell's equations and are thus less accurate but require less computational resources and time. Asymptotic techniques can thus be very valuable for the prediction of bistatic RCS of electrically large targets, due to the decreased computational requirements. This study extends previous work by validating the accuracy of asymptotic techniques to predict bistatic RCS through comparison with full-wave simulations as well as measurements. Validation is done with canonical structures as well as complex realistic aircraft models instead of only looking at a complex slicy structure. The slicy structure is a combination of canonical structures, including cylinders, corner reflectors and cubes. Validation is done over large bistatic angles and at different polarizations. Bistatic RCS measurements were conducted in a compact range, at the University of Pretoria, South Africa. The measurements were performed at different polarizations from 2 GHz to 6 GHz. Fixed bistatic angles of β = 30.8°, 45° and 90° were used. The measurements were calibrated with an active calibration target. The EM simulation tool FEKO was used to generate simulated results. The full-wave multi-level fast multipole method (MLFMM) simulated results together with the measured data were used as reference for validation. The accuracy of physical optics (PO) and geometrical optics (GO) was investigated. Differences relating to amplitude, lobing structure and null positions were observed between the asymptotic, full-wave and measured data. PO and GO were more accurate at angles close to the specular scattering directions and the accuracy seemed to decrease as the bistatic angle increased. At large bistatic angles PO did not perform well due to the shadow regions not being treated appropriately. PO also did not perform well for canonical structures where multi-bounce was the main scattering mechanism. PO and GO do not account for diffraction but these inaccuracies tended to decrease as the electrical size of objects increased. It was evident that both asymptotic techniques do not properly account for bistatic structural shadowing. Specular scattering was calculated accurately even if targets did not meet the electrically large criteria. It was evident that the bistatic RCS prediction performance of PO and GO depends on incident angle, frequency, target shape and observation angle. The improved computational efficiency of the asymptotic solvers yields a major advantage over full-wave solvers and measurements; however, there is still much room for improvement of the accuracy of these asymptotic techniques.

Keywords: asymptotic techniques, bistatic RCS, geometrical optics, physical optics

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2616 Performance Evaluation of Various Displaced Left Turn Intersection Designs

Authors: Hatem Abou-Senna, Essam Radwan

Abstract:

With increasing traffic and limited resources, accommodating left-turning traffic has been a challenge for traffic engineers as they seek balance between intersection capacity and safety; these are two conflicting goals in the operation of a signalized intersection that are mitigated through signal phasing techniques. Hence, to increase the left-turn capacity and reduce the delay at the intersections, the Florida Department of Transportation (FDOT) moves forward with a vision of optimizing intersection control using innovative intersection designs through the Transportation Systems Management & Operations (TSM&O) program. These alternative designs successfully eliminate the left-turn phase, which otherwise reduces the conventional intersection’s (CI) efficiency considerably, and divide the intersection into smaller networks that would operate in a one-way fashion. This study focused on the Crossover Displaced Left-turn intersections (XDL), also known as Continuous Flow Intersections (CFI). The XDL concept is best suited for intersections with moderate to high overall traffic volumes, especially those with very high or unbalanced left turn volumes. There is little guidance on determining whether partial XDL intersections are adequate to mitigate the overall intersection condition or full XDL is always required. The primary objective of this paper was to evaluate the overall intersection performance in the case of different partial XDL designs compared to a full XDL. The XDL alternative was investigated for 4 different scenarios; partial XDL on the east-west approaches, partial XDL on the north-south approaches, partial XDL on the north and east approaches and full XDL on all 4 approaches. Also, the impact of increasing volume on the intersection performance was considered by modeling the unbalanced volumes with 10% increment resulting in 5 different traffic scenarios. The study intersection, located in Orlando Florida, is experiencing recurring congestion in the PM peak hour and is operating near capacity with volume to a capacity ratio closer to 1.00 due to the presence of two heavy conflicting movements; southbound and westbound. The results showed that a partial EN XDL alternative proved to be effective and compared favorably to a full XDL alternative followed by the partial EW XDL alternative. The analysis also showed that Full, EW and EN XDL alternatives outperformed the NS XDL and the CI alternatives with respect to the throughput, delay and queue lengths. Significant throughput improvements were remarkable at the higher volume level with percent increase in capacity of 25%. The percent reduction in delay for the critical movements in the XDL scenarios compared to the CI scenario ranged from 30-45%. Similarly, queue lengths showed percent reduction in the XDL scenarios ranging from 25-40%. The analysis revealed how partial XDL design can improve the overall intersection performance at various demands, reduce the costs associated with full XDL and proved to outperform the conventional intersection. However, partial XDL serving low volumes or only one of the critical movements while other critical movements are operating near or above capacity do not provide significant benefits when compared to the conventional intersection.

Keywords: continuous flow intersections, crossover displaced left-turn, microscopic traffic simulation, transportation system management and operations, VISSIM simulation model

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2615 Identification of Rare Mutations in Genes Involved in Monogenic Forms of Obesity and Diabetes in Obese Guadeloupean Children through Next-Generation Sequencing

Authors: Lydia Foucan, Laurent Larifla, Emmanuelle Durand, Christine Rambhojan, Veronique Dhennin, Jean-Marc Lacorte, Philippe Froguel, Amelie Bonnefond

Abstract:

In the population of Guadeloupe Island (472,124 inhabitants and 80% of subjects of African descent), overweight and obesity were estimated at 23% and 9% respectively among children. High prevalence of diabetes has been reported (~10%) in the adult population. Nevertheless, no study has investigated the contribution of gene mutations to childhood obesity in this population. We aimed to investigate rare genetic mutations in genes involved in monogenic obesity or diabetes in obese Afro-Caribbean children from Guadeloupe Island using next-generation sequencing. The present investigation included unrelated obese children, from a previous study on overweight conducted in Guadeloupe Island in 2013. We sequenced coding regions of 59 genes involved in monogenic obesity or diabetes. A total of 25 obese schoolchildren (with Z-score of body mass index [BMI]: 2.0 to 2.8) were screened for rare mutations (non-synonymous, splice-site, or insertion/deletion) in 59 genes. Mean age of the study population was 12.4 ± 1.1 years. Seventeen children (68%) had insulin-resistance (HOMA-IR > 3.16). A family history of obesity (mother or father) was observed in eight children and three of the accompanying parent presented with type 2 diabetes. None of the children had gonadotrophic abnormality or mental retardation. We detected five rare heterozygous mutations, in four genes involved in monogenic obesity, in five different obese children: MC4R p.Ile301Thr and SIM1 p.Val326Thrfs*43 mutations which were pathogenic; SIM1 p.Ser343Pro and SH2B1 p.Pro90His mutations which were likely pathogenic; and NTRK2 p.Leu140Phe that was of uncertain significance. In parallel, we identified seven carriers of mutation in ABCC8 or KCNJ11 (involved in monogenic diabetes), which were of uncertain significance (KCNJ11 p.Val13Met, KCNJ11 p.Val151Met, ABCC8 p.Lys1521Asn and ABCC8 p.Ala625Val). Rare pathogenic or likely pathogenic mutations, linked to severe obesity were detected in more than 15% of this Afro-Caribbean population at high risk of obesity and type 2 diabetes.

Keywords: childhood obesity, MC4R, monogenic obesity, SIM1

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2614 Identification of New Familial Breast Cancer Susceptibility Genes: Are We There Yet?

Authors: Ian Campbell, Gillian Mitchell, Paul James, Na Li, Ella Thompson

Abstract:

The genetic cause of the majority of multiple-case breast cancer families remains unresolved. Next generation sequencing has emerged as an efficient strategy for identifying predisposing mutations in individuals with inherited cancer. We are conducting whole exome sequence analysis of germ line DNA from multiple affected relatives from breast cancer families, with the aim of identifying rare protein truncating and non-synonymous variants that are likely to include novel cancer predisposing mutations. Data from more than 200 exomes show that on average each individual carries 30-50 protein truncating mutations and 300-400 rare non-synonymous variants. Heterogeneity among our exome data strongly suggest that numerous moderate penetrance genes remain to be discovered, with each gene individually accounting for only a small fraction of families (~0.5%). This scenario marks validation of candidate breast cancer predisposing genes in large case-control studies as the rate-limiting step in resolving the missing heritability of breast cancer. The aim of this study is to screen genes that are recurrently mutated among our exome data in a larger cohort of cases and controls to assess the prevalence of inactivating mutations that may be associated with breast cancer risk. We are using the Agilent HaloPlex Target Enrichment System to screen the coding regions of 168 genes in 1,000 BRCA1/2 mutation-negative familial breast cancer cases and 1,000 cancer-naive controls. To date, our interim analysis has identified 21 genes which carry an excess of truncating mutations in multiple breast cancer families versus controls. Established breast cancer susceptibility gene PALB2 is the most frequently mutated gene (13/998 cases versus 0/1009 controls), but other interesting candidates include NPSR1, GSN, POLD2, and TOX3. These and other genes are being validated in a second cohort of 1,000 cases and controls. Our experience demonstrates that beyond PALB2, the prevalence of mutations in the remaining breast cancer predisposition genes is likely to be very low making definitive validation exceptionally challenging.

Keywords: predisposition, familial, exome sequencing, breast cancer

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2613 Vital Pulp Therapy: A Paradigm Shift in Treating Irreversible Pulpitis

Authors: Fadwa Chtioui

Abstract:

Vital Pulp Therapy (VPT) is nowadays challenging the deep-rooted dogma of root canal treatment, being the only therapeutic option for permanent teeth diagnosed with irreversible pulpitis or carious pulp exposure. Histologic and clinical research has shown that compromised dental pulp can be treated without the full removal or excavation of all healthy pulp, and the outcome of the partial or full pulpotomy followed by a Tricalcium-Silicate-based dressing seems to show promising results in maintaining pulp vitality and preserving affected teeth in the long term. By reviewing recent advances in the techniques of VPT and their clinical effectiveness and safety in permanent teeth with irreversible Pulpitis, this work provides a new understanding of pulp pathophysiology and defense mechanisms and will reform dental practitioners' decision-making in treating irreversible pulpits from root canal therapy to vital pulp therapy by taking advantage of the biological effects of Tricalcium Silicate materials.

Keywords: irreversible pulpitis, vital pulp therapy, pulpotomy, Tricalcium Silicate

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2612 Integration of Microarray Data into a Genome-Scale Metabolic Model to Study Flux Distribution after Gene Knockout

Authors: Mona Heydari, Ehsan Motamedian, Seyed Abbas Shojaosadati

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Prediction of perturbations after genetic manipulation (especially gene knockout) is one of the important challenges in systems biology. In this paper, a new algorithm is introduced that integrates microarray data into the metabolic model. The algorithm was used to study the change in the cell phenotype after knockout of Gss gene in Escherichia coli BW25113. Algorithm implementation indicated that gene deletion resulted in more activation of the metabolic network. Growth yield was more and less regulating gene were identified for mutant in comparison with the wild-type strain.

Keywords: metabolic network, gene knockout, flux balance analysis, microarray data, integration

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2611 Exploring Fluoroquinolone-Resistance Dynamics Using a Distinct in Vitro Fermentation Chicken Caeca Model

Authors: Bello Gonzalez T. D. J., Setten Van M., Essen Van A., Brouwer M., Veldman K. T.

Abstract:

Resistance to fluoroquinolones (FQ) has evolved increasingly over the years, posing a significant challenge for the treatment of human infections, particularly gastrointestinal tract infections caused by zoonotic bacteria transmitted through the food chain and environment. In broiler chickens, a relatively high proportion of FQ resistance has been observed in Escherichia coli indicator, Salmonella and Campylobacter isolates. We hypothesize that flumequine (Flu), used as a secondary choice for the treatment of poultry infections, could potentially be associated with a high proportion of FQ resistance. To evaluate this hypothesis, we used an in vitro fermentation chicken caeca model. Two continuous single-stage fermenters were used to simulate in real time the physiological conditions of the chicken caeca microbial content (temperature, pH, caecal content mixing, and anoxic environment). A pool of chicken caecal content containing FQ-resistant E. coli obtained from chickens at slaughter age was used as inoculum along with a spiked FQ-susceptible Campylobacter jejuni strain isolated from broilers. Flu was added to one of the fermenters (Flu-fermenter) every 24 hours for two days to evaluate the selection and maintenance of FQ resistance over time, while the other served as a control (C-Fermenter). The experiment duration was 5 days. Samples were collected at three different time points: before, during and after Flu administration. Serial dilutions were plated on Butzler culture media with and without Flu (8mg/L) and enrofloxacin (4mg/L) and on MacConkey culture media with and without Flu (4mg/L) and enrofloxacin (1mg/L) to determine the proportion of resistant strains over time. Positive cultures were identified by mass spectrometry and matrix-assisted laser desorption/ionization (MALDI). A subset of the obtained isolates were used for Whole Genome Sequencing analysis. Over time, E. coli exhibited positive growth in both fermenters, while C. jejuni growth was detected up to day 3. The proportion of Flu-resistant E. coli strains recovered remained consistent over time after antibiotic selective pressure, while in the C-fermenter, a decrease was observed at day 5; a similar pattern was observed in the enrofloxacin-resistant E. coli strains. This suggests that Flu might play a role in the selection and persistence of enrofloxacin resistance, compared to C-fermenter, where enrofloxacin-resistant E. coli strains appear at a later time. Furthermore, positive growth was detected from both fermenters only on Butzler plates without antibiotics. A subset of C. jejuni strains from the Flu-fermenter revealed that those strains were susceptible to ciprofloxacin (MIC < 0.12 μg/mL). A selection of E. coli strains from both fermenters revealed the presence of plasmid-mediated quinolone resistance (PMQR) (qnr-B19) in only one strain from the C-fermenter belonging to sequence type (ST) 48, and in all from Flu-fermenter belonged to ST189. Our results showed that Flu selective impact on PMQR-positive E. coli strains, while no effect was observed in C. jejuni. Maintenance of Flu-resistance was correlated with antibiotic selective pressure. Further studies into antibiotic resistance gene transfer among commensal and zoonotic bacteria in the chicken caeca content may help to elucidate the resistance spread mechanisms.

Keywords: fluoroquinolone-resistance, escherichia coli, campylobacter jejuni, in vitro model

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2610 Model Based Simulation Approach to a 14-Dof Car Model Using Matlab/Simulink

Authors: Ishit Sheth, Chandrasekhar Jinendran, Chinmaya Ranjan Sahu

Abstract:

A fourteen degree of freedom (DOF) ride and handling control mathematical model is developed for a car using generalized boltzmann hamel equation which will create a basis for design of ride and handling controller. Mathematical model developed yield equations of motion for non-holonomic constrained systems in quasi-coordinates. The governing differential equation developed integrates ride and handling control of car. Model-based systems engineering approach is implemented for simulation using matlab/simulink, vehicle’s response in different DOF is examined and later validated using commercial software (ADAMS). This manuscript involves detailed derivation of full car vehicle model which provides response in longitudinal, lateral and yaw motion to demonstrate the advantages of the developed model over the existing dynamic model. The dynamic behaviour of the developed ride and handling model is simulated for different road conditions.

Keywords: Full Vehicle Model, MBSE, Non Holonomic Constraints, Boltzmann Hamel Equation

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2609 Analyses and Optimization of Physical and Mechanical Properties of Direct Recycled Aluminium Alloy (AA6061) Wastes by ANOVA Approach

Authors: Mohammed H. Rady, Mohd Sukri Mustapa, S Shamsudin, M. A. Lajis, A. Wagiman

Abstract:

The present study is aimed at investigating microhardness and density of aluminium alloy chips when subjected to various settings of preheating temperature and preheating time. Three values of preheating temperature were taken as 450 °C, 500 °C, and 550 °C. On the other hand, three values of preheating time were chosen (1, 2, 3) hours. The influences of the process parameters (preheating temperature and time) were analyzed using Design of Experiments (DOE) approach whereby full factorial design with center point analysis was adopted. The total runs were 11 and they comprise of two factors of full factorial design with 3 center points. The responses were microhardness and density. The results showed that the density and microhardness increased with decreasing the preheating temperature. The results also found that the preheating temperature is more important to be controlled rather than the preheating time in microhardness analysis while both the preheating temperature and preheating time are important in density analysis. It can be concluded that setting temperature at 450 °C for 1 hour resulted in the optimum responses.

Keywords: AA6061, density, DOE, hot extrusion, microhardness

Procedia PDF Downloads 335
2608 On Strengthening Program of Sixty Years Old Dome Using Carbon Fiber

Authors: Humayun R. H. Kabir

Abstract:

A reinforced concrete dome-built 60 years ago- of circular shape of diameter of 30 m was in distressed conditions due to adverse weathering effects, such as high temperature, wind, and poor maintenance. It was decided to restore the dome to its full strength for future use. A full material strength and durability check including petrography test were conducted. It was observed that the concrete strength was in acceptable range, while bars were corroded more than 40% to their original configurations. Widespread cracks were almost in every meter square. A strengthening program with filling the cracks by injection method, and carbon fiber layup and wrap was considered. Ultra Sound Pulse Velocity (UPV) test was conducted to observe crack depth. Ground Penetration Radar (GPR) test was conducted to observe internal bar conditions and internal cracks. Finally, a load test was conducted to certify the carbon fiber effectiveness, injection method procedure and overall behavior of dome.

Keywords: dome, strengthening program, carbon fiber, load test

Procedia PDF Downloads 233
2607 Fastidious Enteric Pathogens in HIV

Authors: S. Pathak, R. Lazarus

Abstract:

A 25-year-old male HIV patient (CD4 cells 20/µL and HIV viral load 14200000 copies/ml) with a past medical history of duodenal ulcer, pneumocystis carinii pneumonia, oesophageal candidiasis presented with fever and a seizure to hospital. The only recent travel had been a religious pilgrimage from Singapore to Malaysia 5 days prior; during the trip he sustained skin abrasions. The patient had recently started highly active antiretroviral therapy 2 months prior. Clinical examination was unremarkable other than a temperature of 38.8°C and perianal warts. Laboratory tests showed a leukocyte count 12.5x109 cells/L, haemoglobin 9.4 g/dL, normal biochemistry and a C-reactive protein 121 mg/L. CT head and MRI head were unremarkable and cerebrospinal fluid analysis performed after a delay (due to technical difficulties) of 11 days was unremarkable. Blood cultures (three sets) taken on admission showed Gram-negative rods in the anaerobic bottles only at the end of incubation with culture result confirmed by molecular sequencing showing Helicobacter cinaedi. The patient was treated empirically with ceftriaxone for seven days and this was converted to oral co-amoxiclav for a further seven days after the blood cultures became positive. A Transthoracic echocardiogram was unremarkable. The patient made a full recovery. Helicobacter cinaedi is a gram-negative anaerobic fastidious organism affecting patients with comorbidity. Infection may manifest as cellulitius, colitis or as in this case as bloodstream infection – the latter is often attributed to faeco-oral infection. Laboratory identification requires prolonged culture. Therapeutic options may be limited by resistance to macrolides and fluoroquinolones. The likely pathogen inoculation routes in the case described include gastrointestinal translocation due to proctitis at the site of perianal warts, or breach of the skin via abrasions occurring during the pilgrimage. Such organisms are increasing in prevalence as our patient population ages and patients have multiple comorbidities including HIV. It may be necessary in patients with unexplained fever to prolong incubation of sterile sites including blood in order to identify this unusual fastidious organism.

Keywords: fastidious, Helicobacter cinaedi, HIV, immunocompromised

Procedia PDF Downloads 363
2606 Evaluating the Management of Febrile Infants (Less than 90 Days) Presenting to Tallaght Ed- Completed Audit Cycle

Authors: Amel Osman, Stewart McKenna

Abstract:

Aim: Fever may present as the sole sign of a serious underlying infection in young infants. Febrile Infants aged less than 90 days are at an elevated susceptibility to invasive bacterial infections, thus presenting a challenge in ensuring the appropriate management of these cases. This study aims to ensure strict adherence to NICE guidelines for the management of fever in infants between 0 and 90 days presenting to Tallaght Hospital ED. A comprehensive audit, followed by a re-audit, was conducted to enhance the quality of care delivered to these patients. In accordance with NICE guidelines, all febrile infants should undergo blood tests. Additionally, LP should be performed in all neonates under 28 days, infants displaying signs of illness, and those with WCC below 5 or above 15. Method: A retrospective case review was performed, encompassing all patients aged between 0 to 90 days who presented with fever at Tallaght ED. Data retrieval was conducted from electronic records on two separate occasions, six months apart. The evaluation encompassed the assessment of body temperature as well as both partial and full septic workups. Results: Over the study period, 150 infants presented to the ED with fever in the initial audit, and 120 in the re-audit. In the first study, 81 patients warranted a full septic workup as per NICE, but only 48 received it. Conversely, 40 patients met criteria for a partial septic workup, with 12 undergoing blood tests. In the second study, 73 patients qualified for a full septic workup, of which 52 were completed. Additionally, 27 patients were indicated for a partial workup, with 20 undergoing blood tests. Conclusion: Managing febrile infants under three months of age presenting to Tallaght ED remains a persistent challenge, underscoring the need for continuous educational initiatives to guarantee that these patients receive the requisite assessments and treatments.

Keywords: infants, fever, septic workup, tallaght

Procedia PDF Downloads 31
2605 Examining Relationship between Programming Performance, Programming Self Efficacy and Math Success

Authors: Mustafa Ekici, Sacide Güzin Mazman

Abstract:

Programming is the one of ability in computer science fields which is generally perceived difficult by students and various individual differences have been implicated in that ability success. Although several factors that affect programming ability have been identified over the years, there is not still a full understanding of why some students learn to program easily and quickly while others find it complex and difficult. Programming self-efficacy and mathematic success are two of those essential individual differences which are handled as having important effect on the programming success. This study aimed to identify the relationship between programming performance, programming self efficacy and mathematics success. The study group is consisted of 96 undergraduates from Department of Econometrics of Uşak University. 38 (39,58%) of the participants are female while 58 (60,41%) of them are male. Study was conducted in the programming-I course during 2014-2015 fall term. Data collection tools are comprised of programming course final grades, programming self efficacy scale and a mathematics achievement test. Data was analyzed through correlation analysis. The result of study will be reported in the full text of the study.

Keywords: programming performance, self efficacy, mathematic success, computer science

Procedia PDF Downloads 483
2604 Tuberculosis in Humans and Animals in the Eastern Part of the Sudan

Authors: Yassir Adam Shuaib, Stefan Niemann, Eltahir Awad Khalil, Ulrich Schaible, Lothar Heinz Wieler, Mohammed Ahmed Bakhiet, Abbashar Osman Mohammed, Mohamed Abdelsalam Abdalla, Elvira Richter

Abstract:

Tuberculosis (TB) is a chronic bacterial disease of humans and animals and it is characterized by the progressive development of specific granulomatous tubercle lesions in affected tissues. In a six-month study, from June to November 2014, a total of 2,304 carcasses of cattle, camel, sheep, and goats slaughtered at East and West Gaash slaughterhouses, Kassala, were investigated during postmortem, in parallel, 101 sputum samples from TB suspected patients at Kassala and El-Gadarif Teaching Hospitals were collected in order to investigate tuberculosis in animals and humans. Only 0.1% carcasses were found with suspected TB lesions in the liver and lung and peritoneal cavity of two sheep and no tuberculous lesions were found in the carcasses of cattle, goats or camels. All samples, tissue lesions and sputum, were decontaminated by the NALC-NaOH method and cultured for mycobacterial growth at the NRZ for Mycobacteria, Research Center Borstel, Germany. Genotyping and molecular characterization of the grown strains were done by line probe assay (GenoType CM and MTBC) and 16S rDNA, rpoB gene, and ITS sequencing, spoligotyping, MIRU-VNTR typing and next generation sequencing (NGS). Culture of the specimens revealed growth of organisms from 81.6% of all samples. Mycobacterium tuberculosis (76.2%), M. intracellulare (14.2%), mixed infection with M. tuberculosis and M. intracellulare (6.0%) and mixed infection with M. tuberculosis and M. fortuitum and with M. intracellulare and unknown species (1.2%) were detected in the sputum samples and unknown species (1.2%) were detected in the samples of one of the animals tissues. From the 69 M. tuberculosis strains, 25 (36.2%) were showing either mono-drug-resistant or multi-drug-resistant or poly-drug-resistant but none was extensively drug-resistant. In conclusion, the prevalence of TB in animals was very low while in humans M. tuberculosis-Delhi/CAS lineage was responsible for most cases and there was an evidence of MDR transmission and acquisition.

Keywords: animal, human, slaughterhouse, Sudan, tuberculosis

Procedia PDF Downloads 347
2603 Data Analysis for Taxonomy Prediction and Annotation of 16S rRNA Gene Sequences from Metagenome Data

Authors: Suchithra V., Shreedhanya, Kavya Menon, Vidya Niranjan

Abstract:

Skin metagenomics has a wide range of applications with direct relevance to the health of the organism. It gives us insight to the diverse community of microorganisms (the microbiome) harbored on the skin. In the recent years, it has become increasingly apparent that the interaction between skin microbiome and the human body plays a prominent role in immune system development, cancer development, disease pathology, and many other biological implications. Next Generation Sequencing has led to faster and better understanding of environmental organisms and their mutual interactions. This project is studying the human skin microbiome of different individuals having varied skin conditions. Bacterial 16S rRNA data of skin microbiome is downloaded from SRA toolkit provided by NCBI to perform metagenomics analysis. Twelve samples are selected with two controls, and 3 different categories, i.e., sex (male/female), skin type (moist/intermittently moist/sebaceous) and occlusion (occluded/intermittently occluded/exposed). Quality of the data is increased using Cutadapt, and its analysis is done using FastQC. USearch, a tool used to analyze an NGS data, provides a suitable platform to obtain taxonomy classification and abundance of bacteria from the metagenome data. The statistical tool used for analyzing the USearch result is METAGENassist. The results revealed that the top three abundant organisms found were: Prevotella, Corynebacterium, and Anaerococcus. Prevotella is known to be an infectious bacterium found on wound, tooth cavity, etc. Corynebacterium and Anaerococcus are opportunist bacteria responsible for skin odor. This result infers that Prevotella thrives easily in sebaceous skin conditions. Therefore it is better to undergo intermittently occluded treatment such as applying ointments, creams, etc. to treat wound for sebaceous skin type. Exposing the wound should be avoided as it leads to an increase in Prevotella abundance. Moist skin type individuals can opt for occluded or intermittently occluded treatment as they have shown to decrease the abundance of bacteria during treatment.

Keywords: bacterial 16S rRNA , next generation sequencing, skin metagenomics, skin microbiome, taxonomy

Procedia PDF Downloads 153
2602 Inbreeding Study Using Runs of Homozygosity in Nelore Beef Cattle

Authors: Priscila A. Bernardes, Marcos E. Buzanskas, Luciana C. A. Regitano, Ricardo V. Ventura, Danisio P. Munari

Abstract:

The best linear unbiased predictor (BLUP) is a method commonly used in genetic evaluations of breeding programs. However, this approach can lead to higher inbreeding coefficients in the population due to the intensive use of few bulls with higher genetic potential, usually presenting some degree of relatedness. High levels of inbreeding are associated to low genetic viability, fertility, and performance for some economically important traits and therefore, should be constantly monitored. Unreliable pedigree data can also lead to misleading results. Genomic information (i.e., single nucleotide polymorphism – SNP) is a useful tool to estimate the inbreeding coefficient. Runs of homozygosity have been used to evaluate homozygous segments inherited due to direct or collateral inbreeding and allows inferring population selection history. This study aimed to evaluate runs of homozygosity (ROH) and inbreeding in a population of Nelore beef cattle. A total of 814 animals were genotyped with the Illumina BovineHD BeadChip and the quality control was carried out excluding SNPs located in non-autosomal regions, with unknown position, with a p-value in the Hardy-Weinberg equilibrium lower than 10⁻⁵, call rate lower than 0.98 and samples with the call rate lower than 0.90. After the quality control, 809 animals and 509,107 SNPs remained for analyses. For the ROH analysis, PLINK software was used considering segments with at least 50 SNPs with a minimum length of 1Mb in each animal. The inbreeding coefficient was calculated using the ratio between the sum of all ROH sizes and the size of the whole genome (2,548,724kb). A total of 25.711 ROH were observed, presenting mean, median, minimum, and maximum length of 3.34Mb, 2Mb, 1Mb, and 80.8Mb, respectively. The number of SNPs present in ROH segments varied from 50 to 14.954. The longest ROH length was observed in one animal, which presented a length of 634Mb (24.88% of the genome). Four bulls were among the 10 animals with the longest extension of ROH, presenting 11% of ROH with length higher than 10Mb. Segments longer than 10Mb indicate recent inbreeding. Therefore, the results indicate an intensive use of few sires in the studied data. The distribution of ROH along the chromosomes showed that chromosomes 5 and 6 presented a large number of segments when compared to other chromosomes. The mean, median, minimum, and maximum inbreeding coefficients were 5.84%, 5.40%, 0.00%, and 24.88%, respectively. Although the mean inbreeding was considered low, the ROH indicates a recent and intensive use of few sires, which should be avoided for the genetic progress of breed.

Keywords: autozygosity, Bos taurus indicus, genomic information, single nucleotide polymorphism

Procedia PDF Downloads 133
2601 PCR Based DNA Analysis in Detecting P53 Mutation in Human Breast Cancer (MDA-468)

Authors: Debbarma Asis, Guha Chandan

Abstract:

Tumor Protein-53 (P53) is one of the tumor suppressor proteins. P53 regulates the cell cycle that conserves stability by preventing genome mutation. It is named so as it runs as 53-kilodalton (kDa) protein on Polyacrylamide gel electrophoresis although the actual mass is 43.7 kDa. Experimental evidence has indicated that P53 cancer mutants loses tumor suppression activity and subsequently gain oncogenic activities to promote tumourigenesis. Tumor-specific DNA has recently been detected in the plasma of breast cancer patients. Detection of tumor-specific genetic materials in cancer patients may provide a unique and valuable tumor marker for diagnosis and prognosis. Commercially available MDA-468 breast cancer cell line was used for the proposed study.

Keywords: tumor protein (P53), cancer mutants, MDA-468, tumor suppressor gene

Procedia PDF Downloads 455
2600 Full Fat Soybean Meal as a Substitute for Soybean Meal in Broiler Rations

Authors: R. M. K. S. Chandana, A. P. D. G. Pathirana, N. Priyankarage, W. A. D. Nayananjalie, S. S. P. Silva

Abstract:

Full fat soybean meal (FFSBM) has been used in many parts of the world together with solvent-extracted soybean meal (SBM) in livestock feeds. Although some local FFSBM is available, their use has not been assessed experimentally. This study was carried out to evaluate the use of local extruded FFSBM in broiler rations. Four treatment diets were formulated by incorporating locally produced FFSBM (0, 10, 20, and 30%) as a replacement for soybean meal (SBM) in a two-phase (starter and finisher) feeding program. Two hundred Hubbard F 15 day old broiler chicks were randomly assigned into four treatments with five replicates per each. Bodyweight gain (BWG), feed intakes (FI), and feed conversion ratio (FCR) were calculated for a period of 42 days. Nutrient utilization in the form of dry matter (DM), energy, nitrogen, and fat retention were estimated by the total collection method in three weeks old broilers. At the end of the experiment, carcass weight was measured, and the dressing percentage was calculated. Data were analyzed using one way analysis of variance (ANOVA) in SAS. There was no significant effect of FFSBM on feed intakes of chicks fed different diets (p > 0.05). Birds fed the control diet, and FF10 (10% FFSBM diet) gained significantly more than that of birds fed FF20 or FF30 diets (p > 0.05). In the finisher period, control birds gained more than all the other treatment birds. FCR was poorer in bird fed higher levels of FFSBM compared to the control or FF10 birds during their early life, but that was not evident in the latter part of the experiment. Treatments did not alter (p > 0.05) the retention of DM and nitrogen, but energy utilization was lowest (p < 0.05) in birds fed with 0% FFSBM, and the highest fat digestibility was observed in birds fed with 30% FFSBM diets. Thus, it can be concluded that FFSBM can be used as a substitute for SBM in broiler rations and could be incorporated up to 10% of the diet safely with no adverse effects on broiler performances.

Keywords: body weight, broiler, digestibility, full fat soybean meal, soybean meal

Procedia PDF Downloads 121
2599 Comparative Study of Mechanical and Corrosion Behaviors on Heat Treated Steel Alloys

Authors: Mario Robinson, Moe Rabea

Abstract:

This research examines the effects of heat treatment processes on the mechanical properties and corrosion resistanceof1045 and 4140 Steel Alloysfor industrial applications. Heat treatment processes of full annealing, normalizing, quenching, and tempering are carried out on the alloy samples. The mechanical and corrosion resistance tests of the heat treated samples are carried out, and the results obtained are related to their SEMmorphologies analysis. The results show that the heat treatment processes have an effect on the tensile strength, impact, and a significant effect on the corrosion resistance of the alloy samples. With respect to the strain characteristics, significant improvement in the ductility of the samples is recorded in the full annealing and alloy tempered samples. Thus, for application requiring strength and ductility, such as in aerospace industries, this tempered heat treated alloy could be used. In addition, the quenched sample shows a significant improvement in hardness.

Keywords: heat treatment, corrosion resistance, steel, industrial appilcations

Procedia PDF Downloads 155
2598 Experimental Study and Neural Network Modeling in Prediction of Surface Roughness on Dry Turning Using Two Different Cutting Tool Nose Radii

Authors: Deba Kumar Sarma, Sanjib Kr. Rajbongshi

Abstract:

Surface finish is an important product quality in machining. At first, experiments were carried out to investigate the effect of the cutting tool nose radius (considering 1mm and 0.65mm) in prediction of surface finish with process parameters of cutting speed, feed and depth of cut. For all possible cutting conditions, full factorial design was considered as two levels four parameters. Commercial Mild Steel bar and High Speed Steel (HSS) material were considered as work-piece and cutting tool material respectively. In order to obtain functional relationship between process parameters and surface roughness, neural network was used which was found to be capable for the prediction of surface roughness within a reasonable degree of accuracy. It was observed that tool nose radius of 1mm provides better surface finish in comparison to 0.65 mm. Also, it was observed that feed rate has a significant influence on surface finish.

Keywords: full factorial design, neural network, nose radius, surface finish

Procedia PDF Downloads 348