Search results for: fish mass mortality
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5365

Search results for: fish mass mortality

1195 Study and Acquisition of the Duality of the Arabic Language

Authors: Oleg Redkin, Olga Bernikova

Abstract:

It is commonly accepted that every language is both pure linguistic phenomenon as well as socially significant communicative system, which exists on the basis of certain society - its collective 'native speaker'. Therefore the language evolution and features besides its own linguistic rules and regulations are also defined by the influence of a number of extra-linguistic factors. The above mentioned statement may be illustrated by the example of the Arabic language which may be characterized by the following peculiarities: - the inner logic of the Arabic language - the 'algebraicity' of its morphological paradigms and grammar rules; - association of the Arabic language with the sacred texts of Islam, its close ties with the pre-Islamic and Islamic cultural heritage - the pre-Islamic poetry and Islamic literature and science; - territorial distribution, which in recent years went far beyond the boundaries of its traditional realm due to the development of new technologies and the spread of mass media, and what is more important, migration processes; - association of the Arabic language with the so called 'Renaissance of Islam'. These peculiarities should be remembered while considering the status of the Modern Standard Arabic (MSA) language or the Classical Arabic (CA) language as well as the Modern Arabic (MA) dialects in synchrony or from the diachronic point of view. Continuity of any system in diachrony on the one hand depends on the level of its ability to adapt itself to changing environment and by its internal ties on the other. Structural durability of language is characterized by its inner logic, hierarchy of paradigms and its grammar rules, as well as continuity of their implementation in acts of everyday communication. Since the Arabic language is both linguistic and social phenomenon the process of the Arabic language acquisition and study should not be focused only on the knowledge about linguistic features or development of communicative skills alone, but must be supplied with the information related to culture, history and religion of peoples of certain region that will expand and enrich competences of the target audience.

Keywords: Arabic, culture, Islam, language

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1194 Sorption of Cesium Ions from Aqueous Solutions by Magnetic Multi-Walled Carbon Nanotubes Functionalized with Zinc Hexacyanoferrate

Authors: H. H. Lee, D. Y. Kim, S. W. Lee, J. H. Kim, J. H. Kim, W. Z. Oh, S. J. Choi

Abstract:

In recent years, carbon nanotubes (CNTs) have been widely employed as a sorbent for the removal of various metal ions from water due to their unique properties such as large surface area, light mass density, high porous and hollow structure, and strong interaction between the pollutant molecules and CNTs. To apply CNTs to the sorption of Cs+ from aqueous solutions, they must first be functionalized to increase their hydrophilicity and therefore, enhance their applicability to the sorption of polar and relatively low-molecular-weight species. The objective of this study is to investigate the preparation of magnetically separable multi-walled carbon nanotubes (MWCNTs-m) as a sorbents for the removal of Cs+ from aqueous solutions. The MWCNTs-m was prepared using pristine MWCNTs and iron precursor Fe(acac)3. For the selective removal of Cs+ from aqueous solutions, the MWCNTs-m was functionalized with zinc hexacyanoferrate (MWCNTs-m-ZnFC). The physicochemical properties of the synthesized sorbents were characterized with various techniques, including transmission electron microscopy (TEM), specific surface area analysis, Fourier transform-infrared (FT-IR) spectroscopy, and vibrating-sample magnetometer. The MWCNTs-m-ZnFC was found to be easily separated from aqueous solutions by using magnetic field. The MWCNTs-m-ZnFC exhibited a high capacity for sorbing Cs+ from aqueous solutions because of their strong affinity for Cs+ and specific surface area. The sorption ability of the MWCNTs-m-ZnFC for Cs+ was maintained even in the presence of co-existing ions (Na+). Considering these results, the CNT-m-ZnFCs have great potential for use as an effective sorbent for the selective removal of radioactive Cs+ ions from aqueous solutions.

Keywords: multi-walled carbon nanotubes, magnetic materials, cesium, zinc hexacyanoferrate, sorption

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1193 Efficiency of a Molecularly Imprinted Polymer for Selective Removal of Chlorpyrifos from Water Samples

Authors: Oya A. Urucu, Aslı B. Çiğil, Hatice Birtane, Ece K. Yetimoğlu, Memet Vezir Kahraman

Abstract:

Chlorpyrifos is an organophosphorus pesticide which can be found in environmental water samples. The efficiency and reuse of a molecularly imprinted polymer (chlorpyrifos - MIP) were investigated for the selective removal of chlorpyrifos residues. MIP was prepared with UV curing thiol-ene polymerization technology by using multifunctional thiol and ene monomers. The thiol-ene curing reaction is a radical induced process, however unlike other photoinitiated polymerization processes, this polymerization process is a free-radical reaction that proceeds by a step-growth mechanism, involving two main steps; a free-radical addition followed by a chain transfer reaction. It assures a very rapidly formation of a uniform crosslinked network with low shrinkage, reduced oxygen inhibition during curing and excellent adhesion. In this study, thiol-ene based UV-curable polymeric materials were prepared by mixing pentaerythritol tetrakis(3-mercaptopropionate), glyoxal bis diallyl acetal, polyethylene glycol diacrylate (PEGDA) and photoinitiator. Chlorpyrifos was added at a definite ratio to the prepared formulation. Chemical structure and thermal properties were characterized by FTIR and thermogravimetric analysis (TGA), respectively. The pesticide analysis was performed by gas chromatography-mass spectrometry (GC-MS). The influences of some analytical parameters such as pH, sample volume, amounts of analyte concentration were studied for the quantitative recoveries of the analyte. The proposed MIP method was applied to the determination of chlorpyrifos in river and tap water samples. The use of the MIP provided a selective and easy solution for removing chlorpyrifos from the water.

Keywords: molecularly imprinted polymers, selective removal, thilol-ene, uv-curable polymer

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1192 The Seedlings Pea (Pisum Sativum L.) Have A High Potential To Be Used As A Promising Condidate For The Study Of Phytoremediation Mechanisms Following An Aromatic Polycyclic Hydrocarbon (Hap) Contamination Such As Naphtalene

Authors: Agoun-bahar Salima

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The environmental variations to which plants are subjected require them to have a strong capacity for adaptation. Some plants are affected by pollutants and are used as pollution indicators; others have the capacity to block, extract, accumulate, transform or degrade the xenobiotic. The diversity of the legume family includes around 20 000 species and offers opportunities for exploitation through their agronomic, dietary and ecological interests. The lack of data on the bioavailability of the Aromatic Polycyclic Hydrocarbon (PAH) in polluted environments, as their passage in the food chains and on the effects of interaction with other pollutants, justifies priority research on this vast family of hydrocarbons. Naphthalene is a PAH formed from two aromatic rings, it is listed and classified as priority pollutant in the list of 16 PAH by the United States Environmental Protection Agency. The aim of this work was to determinate effect of naphthalene at different concentrations on morphological and physiological responses of pea seedlings. At the same time, the behavior of the pollutant in the soil and its fate at the different parts of plant (roots, stems, leaves and fruits) were also recorded by Gas Chromatography/ Mass Spectrometry (GC / MS). In it controlled laboratory studies, plants exposed to naphthalene were able to grow efficiently. From a quantitative analysis, 67% of the naphthalene was removed from the soil and then found on the leaves of the seedlings in just three weeks of cultivation. Interestingly, no trace of naphthalene or its derivatives were detected on the chromatograms corresponding to the dosage of the pollutant at the fruit level after ten weeks of cultivating the seedlings and this for all the pollutant concentrations used. The pea seedlings seem to tolerate the pollutant when it is applied to the soil. In conclusion, the pea represents an interesting biological model in the study of phytoremediation mechanisms.

Keywords: naphtalene, PAH, Pea, phytoremediation, pollution

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1191 Gender, Language and Body: Literary Representations in Popular Culture Narratives

Authors: Eirini Arvanitaki

Abstract:

Romance has incrementally grown in popularity over the last century. The first Mills & Boon romance novel was published in 1909 and since then romance has not only survived but it has become a long standing genre. There are several reasons behind its durability and success. First, its ability to please and appeal to a mass audience. Romance novels are products of commercial success situated in large scale production, especially if one takes into account the high volume of romance novels published, translated and distributed all around the world every month. Second, what has also contributed to keeping the romance genre alive is the content of the books and their effect on the reader. These are stories of two heterosexual individuals who meet, fall in love, face obstacles and successfully overcome them. Through the love plots, the books address anxieties, concerns and everyday troubles that the average reader can identify with. Additionally, the romance novel is a means of escapism from everyday life and responsibilities as well as a short-lived opportunity to enjoy personal time/space and focus on one’s self. Third, the genre’s ability to adapt to the periods and societies in which it is published has also assisted in prolonging its longevity. This paper discusses the ways in which popular romance authors write and engage with the body. Despite the claim that popular romance narratives adjust their contents in accordance with different time periods and social phenomena, the paper highlights the dissimilarities between writing the female and male body and suggests that women romance writers are yet to break free from phallogocentric law. The examination of the projections of the body and the language used to describe it indicates that these narratives are flexible enough to adjust to twenty-first century but only within the limits of their own conventionality.

Keywords: body, gender, language, literary representations, popular romance narratives, taboo

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1190 Hierarchical Porous Carbon Composite Electrode for High Performance Supercapacitor Application

Authors: Chia-Chia Chang, Jhen-Ting Huang, Hu-Cheng Weng, An-Ya Lo

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This study developed a simple hierarchical porous carbon (HPC) synthesis process and used for supercapacitor application. In which, mesopore provides huge specific surface area, meanwhile, macropore provides excellent mass transfer. Thus the hierarchical porous electrode improves the charge-discharge performance. On the other hand, cerium oxide (CeO2) have also got a lot research attention owing to its rich in content, low in price, environmentally friendly, good catalytic properties, and easy preparation. Besides, a rapid redox reaction occurs between trivalent cerium and tetravalent cerium releases oxygen atom and increase the conductivity. In order to prevent CeO2 from disintegration under long-term charge-discharge operation, the CeO2 carbon porous materials were was integrated as composite material in this study. For in the ex-situ analysis, scanning electron microscope (SEM), X-ray diffraction (XRD), transmission electron microscope (TEM) analysis were adopted to identify the surface morphology, crystal structure, and microstructure of the composite. 77K Nitrogen adsorption-desorption analysis was used to analyze the porosity of each specimen. For the in-situ test, cyclic voltammetry (CV) and chronopotentiometry (CP) were conducted by potentiostat to understand the charge and discharge properties. Ragone plot was drawn to further analyze the resistance properties. Based on above analyses, the effect of macropores/mespores and the CeO2/HPC ratios on charge-discharge performance were investigated. As a result, the capacitance can be greatly enhanced by 2.6 times higher than pristine mesoporous carbon electrode.

Keywords: hierarchical porous carbon, cerium oxide, supercapacitor

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1189 Does Creatine Supplementation Improve Swimming Performance?

Authors: Catrin Morgan, Atholl Johnston

Abstract:

Creatine supplementation should theoretically increase total muscle creatine and so enhance the generation of intramuscular phosphocreatine and subsequent ATP formation. The use of creatine as a potential ergogenic aid in sport has been an area of significant scientific research for a number of years. However the effect of creatine supplementation and swimming performance is a relatively new area of research and is the subject of this review. In swimming creatine supplementation could help maintain maximal power output, aid recovery and increase lean body mass. After investigating the underlying theory and science behind creatine supplementation, a literature review was conducted to identify the best evidence looking at the effect of creatine supplementation on swimming performance. The search identified 27 potential studies, and of these 17 were selected for review. The studies were then categorised into single sprint performance, which involves swimming a short distance race, or repeated interval performance, which involves swimming a series of sprints with intervals of rest between them. None of the studies on the effect of creatine controlled for the multiple confounding factors associated with measurement of swimming performance. The sample size in the studies was limited and this reduced the reliability of the studies and introduced the possibility of bias. The studies reviewed provided insufficient evidence to determine if creatine supplementation is beneficial to swimming performance. However, what data there was supported the use of creatine supplementation in repeated interval swimming rather than in single sprint swimming. From a review of the studies, it was calculated on average, there was a 1.37% increase in swimming performance with the use of creatine for repeated intervals and a 0.86% increase in performance for single sprint. While this may seem minor, it should be remembered that swimming races are often won by much smaller margins. In the 2012 London Olympics the Men’s 100 metres freestyle race was won by a margin of only 0.01 of a second. Therefore any potential benefit could make a dramatic difference to the final outcome of the race. Overall more research is warranted before the benefits of creatine supplementation in swimming performance can be further clarified.

Keywords: creatine supplementation, repeated interval, single sprint, swimming performance

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1188 Film Review of 'Heroic Saviours and Survivors': The Representation of Sex Trafficking in Popular Films in India

Authors: Nisha James, Shubha Ranganathan

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One of the most poignant forms of organized crime against women, which has rarely made it to the world of Indian cinema, is that of sex trafficking, i.e. the forcible involvement of women in the sex trade through fraud or coercion (Hughes, 2005). In the space of Indian cinema, much of the spotlight has been on the sensational drug trafficking and gang mafia of Bombay. During our research on sex trafficking, the rehabilitated women interviewed often expressed strong criticism about mass media’s naive portrayal of prostitutes as money-minting, happy and sexually driven women. They argued that this unrealistic portrayal ignored the fact that this was not a reality for the majority of trafficked women. Given the gravity of sex trafficking as a human rights issue, it is, therefore, refreshing to see three recent films on sex trafficking in Indian Languages – Naa Bangaaru Talli (2014, Telugu), Mardaani (2014, Hindi) and Lakshmi (2014, Hindi). This paper reviews these three films to explore the portrayal of the everyday reality of trafficking for women. Film analysis was used to understand the representation of psychological issues in the media. The strength of these movies starts with their inspirations which are of true stories and that they are all aimed at bringing awareness about the issue of sex trafficking, which is a rising social evil in Indian society though none of the three films move to portray the next phase of rehabilitation and reintegration of victims, which is a very complex and important process in the life of a survivor. According to findings, survivors of sex trafficking find the rehabilitation and reintegration into society to be a slow and tough part of their life as they continuously face stigma and social exclusion and have to strive to live against all odds of non-acceptance starting from their family.

Keywords: film review, Indian films, sex trafficking, survivors

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1187 Preparation of Papers - Developing a Leukemia Diagnostic System Based on Hybrid Deep Learning Architectures in Actual Clinical Environments

Authors: Skyler Kim

Abstract:

An early diagnosis of leukemia has always been a challenge to doctors and hematologists. On a worldwide basis, it was reported that there were approximately 350,000 new cases in 2012, and diagnosing leukemia was time-consuming and inefficient because of an endemic shortage of flow cytometry equipment in current clinical practice. As the number of medical diagnosis tools increased and a large volume of high-quality data was produced, there was an urgent need for more advanced data analysis methods. One of these methods was the AI approach. This approach has become a major trend in recent years, and several research groups have been working on developing these diagnostic models. However, designing and implementing a leukemia diagnostic system in real clinical environments based on a deep learning approach with larger sets remains complex. Leukemia is a major hematological malignancy that results in mortality and morbidity throughout different ages. We decided to select acute lymphocytic leukemia to develop our diagnostic system since acute lymphocytic leukemia is the most common type of leukemia, accounting for 74% of all children diagnosed with leukemia. The results from this development work can be applied to all other types of leukemia. To develop our model, the Kaggle dataset was used, which consists of 15135 total images, 8491 of these are images of abnormal cells, and 5398 images are normal. In this paper, we design and implement a leukemia diagnostic system in a real clinical environment based on deep learning approaches with larger sets. The proposed diagnostic system has the function of detecting and classifying leukemia. Different from other AI approaches, we explore hybrid architectures to improve the current performance. First, we developed two independent convolutional neural network models: VGG19 and ResNet50. Then, using both VGG19 and ResNet50, we developed a hybrid deep learning architecture employing transfer learning techniques to extract features from each input image. In our approach, fusing the features from specific abstraction layers can be deemed as auxiliary features and lead to further improvement of the classification accuracy. In this approach, features extracted from the lower levels are combined into higher dimension feature maps to help improve the discriminative capability of intermediate features and also overcome the problem of network gradient vanishing or exploding. By comparing VGG19 and ResNet50 and the proposed hybrid model, we concluded that the hybrid model had a significant advantage in accuracy. The detailed results of each model’s performance and their pros and cons will be presented in the conference.

Keywords: acute lymphoblastic leukemia, hybrid model, leukemia diagnostic system, machine learning

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1186 Lipase-Catalyzed Synthesis of Novel Nutraceutical Structured Lipids in Non-Conventional Media

Authors: Selim Kermasha

Abstract:

A process for the synthesis of structured lipids (SLs) by the lipase-catalyzed interesterification of selected endogenous edible oils such as flaxseed oil (FO) and medium-chain triacylglyceols such as tricaprylin (TC) in non-conventional media (NCM), including organic solvent media (OSM) and solvent-free medium (SFM), was developed. The bioconversion yield of the medium-long-medium-type SLs (MLM-SLs were monitored as the responses with use of selected commercial lipases. In order to optimize the interesterification reaction and to establish a model system, a wide range of reaction parameters, including TC to FO molar ratio, reaction temperature, enzyme concentration, reaction time, agitation speed and initial water activity, were investigated to establish the a model system. The model system was monitored with the use of multiple response surface methodology (RSM) was used to obtain significant models for the responses and to optimize the interesterification reaction, on the basis of selected levels and variable fractional factorial design (FFD) with centre points. Based on the objective of each response, the appropriate level combination of the process parameters and the solutions that met the defined criteria were also provided by means of desirability function. The synthesized novel molecules were structurally characterized, using silver-ion reversed-phase high-performance liquid chromatography (RP-HPLC) atmospheric pressure chemical ionization-mass spectrophotometry (APCI-MS) analyses. The overall experimental findings confirmed the formation of dicaprylyl-linolenyl glycerol, dicaprylyl-oleyl glycerol and dicaprylyl-linoleyl glycerol resulted from the lipase-catalyzed interesterification of FO and TC.

Keywords: enzymatic interesterification, non-conventinal media, nutraceuticals, structured lipids

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1185 Missed Opportunities for Immunization of under Five Children in Calabar South County Cros River State, Nigeria, the Way Forward

Authors: Celestine Odigwe, Epoke Lincoln, Rhoda-Dara Ephraim

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Background; Immunization against the childhood killer diseases is the cardinal strategy for the prevention of these diseases all over the world in under five children, these diseases include; Tuberculosis, Measles, Polio, Tetanus, Diphthria, Pertusis, Yellow Fever, Hepatitis B, Haemophilus Influenza type B. 6.9 million children die before their fifth birthday , 80% of the worlds death in children under 5 years occur in 25 countries most in Africa and Asia and 2 million children can be saved each year with routine immunization Therefore failure to achieve total immunization coverage puts several children at risk. Aim; The aim of the study was to ascertain the prevalence, Investigate the various reasons and causes why several under five children in a suburb of calabar municipal county fail to get the required immunizations as at and when due and possibly the consequences, so that efforts can be re-directed towards the solution of the problems so identified. Methods; the study was a community based cross sectional study. The respondents were the mothers/guardians of the sampled children who were all aged 0-59 months. To be eligible for recruitment into the study, the parent or guardian was required to give an informed consent, reside within the Calabar South County with his/her children aged 0-59 months. We calculated our sample size using the Leslie-Kish formula and we used a two-staged sampling method, first to ballot for the wards to be involved and then to select four of the most populated ones in the wards chosen. Data collection was by interviewer administered structured questionnaire (Appendix I), Data collected was entered and analyzed using Statistical Package for the Social Sciences (SPSS) Version 20. Percentages were calculated and represented using charts and tables Results; The number of children sampled was 159. We found that 150 were fully immunized and 9 were not, the prevalence of missed opportunity was 32% from the study. The reasons for missed opportunities were varied, ranging from false contraindications, logistical problems resulting in very poor access roads to health facilities and poor organization of health centers together with negative health worker attitudes. Some of the consequences of these missed opportunities were increased susceptibility to vaccine preventable diseases, resurgence of the above diseases and increased morbidity and mortality of children aged less than 5 years. Conclusion; We found that ignorance on the part of both parents/guardians and health care staff together with infrastructural inadequacies in the county such as- roads, poor electric power supply for storage of vaccines were hugely responsible for most missed opportunities for immunization. The details of these and suggestions for improvement and the way forward are discussed.

Keywords: missed opportunity, immunization, under five, Calabar south

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1184 Assessment of Nutrient Intake, Nutritional Knowledge and Dietary Habits of Omani University Student Athletes

Authors: Amanat Ali, Muhammad S. Al-Siyabi, Mostafa I. Waly, Hashem Al-Kilani

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In a cross-sectional research design, we assessed the nutrient intake, nutritional status, nutritional knowledge and dietary habits of Sultan Qaboos University (SQU) student athletes. A total of 71 (49 male and 22 female) student athletes with a mean age of 21.0 ± 1.81 and 19.32 ± 0.72 years and body mass index (BMI) of 22.51 ± 1.98 and 20.34 ± 2.97 kg/m2 for male and female respectively, participated in this study. A study questionnaire consisting of 2 sections was distributed to the participants. Section I included 18 questions regarding the demographic information, whereas the Section II consisted of 20 questions regarding the nutrition knowledge. The dietary intake of participants was collected by using a 7-days food diary identifying the frequency as well as the variety of food consumption. Significant differences (P < 0.05) were observed in the main sources of nutrition information used by the male and female athletes. Male athletes mainly had most of the nutrition information from friends (17%) whereas female athletes relied mainly on the family (20%). More female athletes (20%) were using TV as a source of nutrition information as compared to male athletes (15%). Both male and female athletes had the minimum nutrition information from dietitians and physicians. Significant (P < 0.05) differences were also observed in the nutritional knowledge and dietary habits scores of male and female athletes, which were 57 % and 49 %, respectively. Male athletes were classified to have fair nutritional knowledge and dietary habits, whereas the female athletes had poor nutritional knowledge and dietary habits. The average daily energy intake of male athletes was 2595 ± 358 kcal/day. Carbohydrate, fat, and protein contributed 64%, 22%, and 14%, of the total energy intake for the male athletes, respectively. The energy and macronutrients intake of male athletes was within the recommended dietary intake. The results indicated some gaps in the nutritional knowledge of SQU student athletes and suggest that there is a need for developing strategies in counseling and teaching the athletes to improve their nutritional knowledge and dietary habits.

Keywords: nutrient assessment, nutritional knowledge, dietary habits, Omani University athletes

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1183 Management Prospects of Winery By-Products Based on Phenolic Compounds and Antioxidant Activity of Grape Skins: The Case of Greek Ionian Islands

Authors: Marinos Xagoraris, Iliada K. Lappa, Charalambos Kanakis, Dimitra Daferera, Christina Papadopoulou, Georgios Sourounis, Charilaos Giotis, Pavlos Bouchagier, Christos S. Pappas, Petros A. Tarantilis, Efstathia Skotti

Abstract:

The aim of this work was to recover phenolic compounds from grape skins produced in Greek varieties of the Ionian Islands in order to form the basis of calculations for their further utilization in the context of the circular economy. Isolation and further utilization of phenolic compounds is an important issue in winery by-products. For this purpose, 37 samples were collected, extracted, and analyzed in an attempt to provide the appropriate basis for their sustainable exploitation. Extraction of the bioactive compounds was held using an eco-friendly, non-toxic, and highly effective water-glycerol solvent system. Then, extracts were analyzed using UV-Vis, liquid chromatography-mass spectrometry (LC-MS), FTIR, and Raman spectroscopy. Also, total phenolic content and antioxidant activity were measured. LC-MS chromatography showed qualitative differences between different varieties. Peaks were attributed to monomeric 3-flavanols as well as monomeric, dimeric, and trimeric proanthocyanidins. The FT-IR and Raman spectra agreed with the chromatographic data and contributed to identifying phenolic compounds. Grape skins exhibited high total phenolic content (TPC), and it was proved that during vinification, a large number of polyphenols remained in the pomace. This study confirmed that grape skins from Ionian Islands are a promising source of bioactive compounds, suggesting their utilization under a bio-economic and environmental strategic framework.

Keywords: antioxidant activity, grape skin, phenolic compounds, waste recovery

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1182 The Development of Liquid Chromatography Tandem Mass Spectrometry Method for Citrinin Determination in Dry-Fermented Meat Products

Authors: Ana Vulic, Tina Lesic, Nina Kudumija, Maja Kis, Manuela Zadravec, Nada Vahcic, Tomaz Polak, Jelka Pleadin

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Mycotoxins are toxic secondary metabolites produced by numerous types of molds. They can contaminate both food and feed so that they represent a serious public health concern. Production of dry-fermented meat products involves ripening, during which molds can overgrow the product surface, produce mycotoxins, and consequently contaminate the final product. Citrinin is a mycotoxin produced mainly by the Penicillium citrinum. Data on citrinin occurrence in both food and feed are limited. Therefore, there is a need for research on citrinin occurrence in these types of meat products. The LC-MS/MS method for citrinin determination was developed and validated. Sample preparation was performed using immunoaffinity columns, which resulted in clean sample extracts. Method validation included the determination of the limit of detection (LOD), the limit of quantification (LOQ), recovery, linearity, and matrix effect in accordance to the latest validation guidance. The determined LOD and LOQ were 0.60 µg/kg and 1.98 µg/kg, respectively, showing a good method sensitivity. The method was tested for its linearity in the calibration range of 1 µg/L to 10 µg/L. The recovery was 100.9 %, while the matrix effect was 0.7 %. This method was employed in the analysis of 47 samples of dry-fermented sausages collected from local households. Citrinin wasn’t detected in any of these samples, probably because of the short ripening period of the tested sausages that takes three months tops. The developed method shall be used to test other types of traditional dry-cured products, such as prosciuttos, whose surface is usually more heavily overgrown by surface molds due to the longer ripening period.

Keywords: citrinin, dry-fermented meat products, LC-MS/MS, mycotoxins

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1181 Sun-Light Driven Photocatalytic Degradation of Tetracycline Antibiotics Employing Hydrothermally Synthesized sno₂/mnv₂o₆ Heterojunction

Authors: Sandeep Kaushal

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Tetracycline (TC) is a widespread antibiotic that is utilised in a multitude of countries, particularly China, India, and the United States of America, due to its low cost and potency in boosting livestock production. Unfortunately, certain antibiotics can be hazardous to living beings due to metal complexation and aggregation, which can lead to teratogenicity and carcinogenicity. Heterojunction photocatalysts are promising for the effective removal of pollutants like antibiotics. Herein, a simple, economical, and pollution-less hydrothermal technique was used to construct SnO₂/MnV₂O₆heterojunction with varying amounts of tin dioxide (SO₂). Various sophisticated techniques like XRD, FTIR, XPS, FESEM, HRTEM, and PLand Raman spectroscopy demonstrated the successful synthesis of SnO₂/MnV₂O₆ heterojunction photocatalysts.BET surface area analysis revealed that the as-synthesized heterojunction has a favorable surface area and surface properties for efficacious degradation of tetracycline. Under the direct sunlight exposure, the SnO₂/MnV₂O₆ heterojunction possessed superior photodegradation activity toward TC than the pristine SnO₂ and MnV2O6owing to their excellent adsorption abilities suitable band positions, large surface areas along with the effective charge-transfer ability of the heterojunction. The SnO₂/MnV₂O₆ heterojunction possessed extraordinary efficiency for the photocatalytic degradation of TC antibiotic (98% in 60 min) with an apparent rate constant of 0.092 min–1. In the degradation experiments, photocatalytic activities of as-synthesized heterojunction were studied by varying different factors such as time contact, catalyst dose, and solution pH. The role of reactive species in antibiotics was validated by radical scavenging studies, which indicated that.OH, radical has a critical role in photocatalytic degradation. Moreover, liquid chromatography-mass spectrometry (LC-MS) investigations were employed to anticipate a plausible mechanism for TC degradation.

Keywords: photocatalytic degradation, tetracycline, heterojunction, LC-MS

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1180 From Talk to Action-Tackling Africa’s Pollution and Climate Change Problem

Authors: Ngabirano Levis

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One of Africa’s major environmental challenges remains air pollution. In 2017, UNICEF estimated over 400,000 children in Africa died as a result of indoor pollution, while 350 million children remain exposed to the risks of indoor pollution due to the use of biomass and burning of wood for cooking. Over time, indeed, the major causes of mortality across Africa are shifting from the unsafe water, poor sanitation, and malnutrition to the ambient and household indoor pollution, and greenhouse gas (GHG) emissions remain a key factor in this. In addition, studies by the OECD estimated that the economic cost of premature deaths due to Ambient Particulate Matter Pollution (APMP) and Household Air Pollution across Africa in 2013 was about 215 Billion US Dollars and US 232 Billion US Dollars, respectively. This is not only a huge cost for a continent where over 41% of the Sub-Saharan population lives on less than 1.9 US Dollars a day but also makes the people extremely vulnerable to the negative climate change and environmental degradation effects. Such impacts have led to extended droughts, flooding, health complications, and reduced crop yields hence food insecurity. Climate change, therefore, poses a threat to global targets like poverty reduction, health, and famine. Despite efforts towards mitigation, air contributors like carbon dioxide emissions are on a generally upward trajectory across Africa. In Egypt, for instance, emission levels had increased by over 141% in 2010 from the 1990 baseline. Efforts like the climate change adaptation and mitigation financing have also hit obstacles on the continent. The International Community and developed nations stress that Africa still faces challenges of limited human, institutional and financial systems capable of attracting climate funding from these developed economies. By using the qualitative multi-case study method supplemented by interviews of key actors and comprehensive textual analysis of relevant literature, this paper dissects the key emissions and air pollutant sources, their impact on the well-being of the African people, and puts forward suggestions as well as a remedial mechanism to these challenges. The findings reveal that whereas climate change mitigation plans appear comprehensive and good on paper for many African countries like Uganda; the lingering political interference, limited research guided planning, lack of population engagement, irrational resource allocation, and limited system and personnel capacity has largely impeded the realization of the set targets. Recommendations have been put forward to address the above climate change impacts that threaten the food security, health, and livelihoods of the people on the continent.

Keywords: Africa, air pollution, climate change, mitigation, emissions, effective planning, institutional strengthening

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1179 Characterization and Monitoring of the Yarn Faults Using Diametric Fault System

Authors: S. M. Ishtiaque, V. K. Yadav, S. D. Joshi, J. K. Chatterjee

Abstract:

The DIAMETRIC FAULTS system has been developed that captures a bi-directional image of yarn continuously in sequentially manner and provides the detailed classification of faults. A novel mathematical framework developed on the acquired bi-directional images forms the basis of fault classification in four broad categories, namely, Thick1, Thick2, Thin and Normal Yarn. A discretised version of Radon transformation has been used to convert the bi-directional images into one-dimensional signals. Images were divided into training and test sample sets. Karhunen–Loève Transformation (KLT) basis is computed for the signals from the images in training set for each fault class taking top six highest energy eigen vectors. The fault class of the test image is identified by taking the Euclidean distance of its signal from its projection on the KLT basis for each sample realization and fault class in the training set. Euclidean distance applied using various techniques is used for classifying an unknown fault class. An accuracy of about 90% is achieved in detecting the correct fault class using the various techniques. The four broad fault classes were further sub classified in four sub groups based on the user set boundary limits for fault length and fault volume. The fault cross-sectional area and the fault length defines the total volume of fault. A distinct distribution of faults is found in terms of their volume and physical dimensions which can be used for monitoring the yarn faults. It has been shown from the configurational based characterization and classification that the spun yarn faults arising out of mass variation, exhibit distinct characteristics in terms of their contours, sizes and shapes apart from their frequency of occurrences.

Keywords: Euclidean distance, fault classification, KLT, Radon Transform

Procedia PDF Downloads 257
1178 Trauma Informed Healthy Lifestyle Program for Young Adults

Authors: Alicia Carranza, Hildemar Dos Santos, W. Lawrence Beeson, R. Patti Herring, Kimberly R. Freeman, Adam Arechiga

Abstract:

Early exposure to trauma can impact health-related behaviors later in life, which poses a considerable challenge for young adults transitioning into independence when they are lacking the necessary skills and support to live a healthy life. The study will be a non-experimental, mixed methods pre- and post-test (where subjects will serve as their own controls) to determine the impact of an eight-week trauma-informed healthy lifestyle program on self-efficacy for adopting health-promoting behaviors and health outcomes among young adults. Forty-two adults, ages 18-24 who are living in Orange County, CA will be recruited to participate in the eight-week trauma-informed healthy living program. Baseline and post-intervention assessments will be conducted to assess changes in self-efficacy for nutrition and physical exercise, sleep quality and quantity, body mass index (kg/m2), and coping skills used by comparing pre- to post-intervention. Some of the planned activities include cooking demonstrations, mindful eating activities and media literacy using Instagram. Frequencies analyses, paired t-test, and multiple regression will be used to determine if there was a change in coping skills. The results of this study can serve to assess the potential for mitigating the effects of Adverse Childhood Experiences (ACEs), or other toxic stress, experienced during adolescence across the lifespan. Young adults who learn how to cope with stress in a healthy way and engage in a healthy lifestyle can be better prepared to role model that behavior to their children.

Keywords: nutrition, healthy lifestyle, trauma-informed, stress management

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1177 Composite 'C' Springs for Anti-Seismic Building Suspension: Positioning 'Virtual Center of Pendulation above Gravity Center'

Authors: Max Sardou, Patricia Sardou

Abstract:

Now that weight saving is mandatory, to author best knowledge composite springs, that we have invented, are best choice for automotive suspensions, against steel. So, we have created a Joint Ventures called S.ARA, in order to mass produce composite coils springs. Start of Production of composite coils springs was in 2014 for AUDI. As we have demonstrated, on the road, that composite springs are not a sweet dream. The present paper describes all the benefits of ‘C’ springs and ‘S’ springs for high performance vehicles suspension, for rocket stage separation, and for satellite injection into orbit. Developing rocket stage separation, we have developed for CNES (Centre National d’Etudes Spatiales) the following concept. If we call ‘line of action’ a line going from one end of a spring to the other. Our concept is to use for instance two springs inclined. In such a way that their line of action cross together and create at this crossing point a virtual center well above the springs. This virtual center, is pulling from above the top stage and is offering a guidance, perfectly stable and straight. About buildings, our solution is to transfer this rocket technology, creating a ‘virtual center’ of pendulation positioned above the building center of gravity. This is achieved by using tilted composite springs benches oriented in such a way that their line of action converges creating the ‘virtual center’. Thanks to the ‘virtual center’ position, the building behaves as a pendulum, hanged from above. When earthquake happen then the building will oscillate around its ‘virtual center’ and will go back safely to equilibrium after the tremor. ‘C’ springs, offering anti-rust, anti-settlement, fail-safe suspension, plus virtual center solution is the must for long-lasting, perfect protection of buildings against earthquakes.

Keywords: virtual center of tilt, composite springs, fail safe springs, antiseismic suspention

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1176 Reduced Glycaemic Impact by Kiwifruit-Based Carbohydrate Exchanges Depends on Both Available Carbohydrate and Non-Digestible Fruit Residue

Authors: S. Mishra, J. Monro, H. Edwards, J. Podd

Abstract:

When a fruit such as kiwifruit is consumed its tissues are released from the physical /anatomical constraints existing in the fruit. During digestion they may expand several-fold to achieve a hydrated solids volume far greater than the original fruit, and occupy the available space in the gut, where they surround and interact with other food components. Within the cell wall dispersion, in vitro digestion of co-consumed carbohydrate, diffusion of digestion products, and mixing responsible for mass transfer of nutrients to the gut wall for absorption, were all retarded. All of the foregoing processes may be involved in the glycaemic response to carbohydrate foods consumed with kiwifruit, such as breakfast cereal. To examine their combined role in reducing the glycaemic response to wheat cereal consumed with kiwifruit we formulated diets containing equal amounts of breakfast cereal, with the addition of either kiwifruit, or sugars of the same composition and quantity as in kiwifruit. Therefore, the only difference between the diets was the presence of non-digestible fruit residues. The diet containing the entire disperse kiwifruit significantly reduced the glycaemic response amplitude and the area under the 0-120 min incremental blood glucose response curve (IAUC), compared with the equicarbohydrate diet containing the added kiwifruit sugars. It also slightly but significantly increased the 120-180 min IAUC by preventing a postprandial overcompensation, indicating improved homeostatic blood glucose control. In a subsequent study in which we used kiwifruit in a carbohydrate exchange format, in which the kiwifruit carbohydrate partially replaced breakfast cereal in equal carbohydrate meals, the blood glucose was further reduced without a loss of satiety, and with a reduction in insulin demand. The results show that kiwifruit may be a valuable component in low glycaemic impact diets.

Keywords: carbohydrate, digestion, glycaemic response, kiwifruit

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1175 Study on the Relationship between Obesity Indicators and Mineral Status in Qatari Adults

Authors: Alaa A. H. Shehada, Eman Abdelnasser Abouhassanein, Reem Mohsen Ali, Joyce J. Moawad, Hiba Bawadi, Abdelhamid Kerkadi

Abstract:

Background: The association between obesity and micronutrient deficiencies is well documented. Among minerals that have been widely studied: zinc, iron and magnesium. Objectives: This study aims to determine the association between obesity indices and mineral status among Qatari adults. Methods: Secondary data was obtained from Qatar Biobank. 414 healthy Qatari aged 20-50 years old were randomly selected from the database. Anthropometric measurements (WC, Weight, and height), body fat, and mineral status (Fe, Mg, Ca, K, Na) were obtained for all selected participants. Differences in anthropometric measurements and mineral status were analyzed by t-test or ANOVA. Spearman correlation coefficients were determined to assess the association between minerals and anthropometric variables. Statistical significance for the hypothesis tests was set at p <0.05. All statistical analysis was preformed using SPSS software version 23.0. Results: Iron, calcium, and sodium levels decreased with an increase in body mass index. Moreover, only iron showed a significant correlation with waist circumference, and waist to height ratio increased. Additionally, calcium, iron, magnesium, and sodium had a statistically significant negative correlation with total body fat percentage and trunk fat percentage. There were statistically significant negative correlations of anthropometrics with minerals. Conclusion: Body fat and trunk fat percentage had a significant inverse relationship with iron, calcium, sodium, and magnesium, while there was no correlation between body fat or trunk fat percentage with potassium.

Keywords: Qatar biobank, body fat distribution, mineral status, Qatari adults

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1174 Deciphering the Action of Neuraminidase in Glioblastoma Models

Authors: Nathalie Baeza-Kallee, Raphaël Bergès, Victoria Hein, Stéphanie Cabaret, Jeremy Garcia, Abigaëlle Gros, Emeline Tabouret, Aurélie Tchoghandjian, Carole Colin, Dominique Figarella-Branger

Abstract:

Glioblastoma (GBM) contains cancer stem cells that are resistant to treatment. GBM cancer stem cell expresses glycolipids recognized by the A2B5 antibody. A2B5, induced by the enzyme ST8 alpha-N-acetyl-neuraminide alpha-2,8-sialyl transferase 3 (ST8Sia3), plays a crucial role in the proliferation, migration, clonogenicity, and tumorigenesis of GBM cancer stem cells. Our aim was to characterize the resulting effects of neuraminidase that remove A2B5 in order to target GBM cancer stem cells. To this end, we set up a GBM organotypic slice model; quantified A2B5 expression by flow cytometry in U87-MG, U87-ST8Sia3, and GBM cancer stem cell lines, treated or not by neuraminidase; performed RNAseq and DNA methylation profiling; and analyzed the ganglioside expression by liquid chromatography-mass spectrometry in these cell lines, treated or not with neuraminidase. Results demonstrated that neuraminidase decreased A2B5 expression, tumor size, and regrowth after surgical removal in the organotypic slice model but did not induce a distinct transcriptomic or epigenetic signature in GBM CSC lines. RNAseq analysis revealed that OLIG2, CHI3L1, TIMP3, TNFAIP2, and TNFAIP6 transcripts were significantly overexpressed in U87-ST8Sia3 compared to U87-MG. RT-qPCR confirmed these results and demonstrated that neuraminidase decreased gene expression in GBM cancer stem cell lines. Moreover, neuraminidase drastically reduced ganglioside expression in GBM cancer stem cell lines. Neuraminidase, by its pleiotropic action, is an attractive local treatment against GBM.

Keywords: cancer stem cell, ganglioside, glioblastoma, targeted treatment

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1173 Influence of Internal Topologies on Components Produced by Selective Laser Melting: Numerical Analysis

Authors: C. Malça, P. Gonçalves, N. Alves, A. Mateus

Abstract:

Regardless of the manufacturing process used, subtractive or additive, material, purpose and application, produced components are conventionally solid mass with more or less complex shape depending on the production technology selected. Aspects such as reducing the weight of components, associated with the low volume of material required and the almost non-existent material waste, speed and flexibility of production and, primarily, a high mechanical strength combined with high structural performance, are competitive advantages in any industrial sector, from automotive, molds, aviation, aerospace, construction, pharmaceuticals, medicine and more recently in human tissue engineering. Such features, properties and functionalities are attained in metal components produced using the additive technique of Rapid Prototyping from metal powders commonly known as Selective Laser Melting (SLM), with optimized internal topologies and varying densities. In order to produce components with high strength and high structural and functional performance, regardless of the type of application, three different internal topologies were developed and analyzed using numerical computational tools. The developed topologies were numerically submitted to mechanical compression and four point bending testing. Finite Element Analysis results demonstrate how different internal topologies can contribute to improve mechanical properties, even with a high degree of porosity relatively to fully dense components. Results are very promising not only from the point of view of mechanical resistance, but especially through the achievement of considerable variation in density without loss of structural and functional high performance.

Keywords: additive manufacturing, internal topologies, porosity, rapid prototyping, selective laser melting

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1172 The Use of Mobile Phone as Enhancement to Mark Multiple Choice Objectives English Grammar and Literature Examination: An Exploratory Case Study of Preliminary National Diploma Students, Abdu Gusau Polytechnic, Talata Mafara, Zamfara State, Nigeria

Authors: T. Abdulkadir

Abstract:

Most often, marking and assessment of multiple choice kinds of examinations have been opined by many as a cumbersome and herculean task to accomplished manually in Nigeria. Usually this may be in obvious nexus to the fact that mass numbers of candidates were known to take the same examination simultaneously. Eventually, marking such a mammoth number of booklets dared and dread even the fastest paid examiners who often undertake the job with the resulting consequences of stress and boredom. This paper explores the evolution, as well as the set aim to envision and transcend marking the Multiple Choice Objectives- type examination into a thing of creative recreation, or perhaps a more relaxing activity via the use of the mobile phone. A more “pragmatic” dimension method was employed to achieve this work, rather than the formal “in-depth research” based approach due to the “novelty” of the mobile-smartphone e-Marking Scheme discovery. Moreover, being an evolutionary scheme, no recent academic work shares a direct same topic concept with the ‘use of cell phone as an e-marking technique’ was found online; thus, the dearth of even miscellaneous citations in this work. Additional future advancements are what steered the anticipatory motive of this paper which laid the fundamental proposition. However, the paper introduces for the first time the concept of mobile-smart phone e-marking, the steps to achieve it, as well as the merits and demerits of the technique all spelt out in the subsequent pages.

Keywords: cell phone, e-marking scheme (eMS), mobile phone, mobile-smart phone, multiple choice objectives (MCO), smartphone

Procedia PDF Downloads 245
1171 A Coupled Stiffened Skin-Rib Fully Gradient Based Optimization Approach for a Wing Box Made of Blended Composite Materials

Authors: F. Farzan Nasab, H. J. M. Geijselaers, I. Baran, A. De Boer

Abstract:

A method is introduced for the coupled skin-rib optimization of a wing box where mass minimization is the objective and local buckling is the constraint. The structure is made of composite materials where continuity of plies in multiple adjacent panels (blending) has to be satisfied. Blending guarantees the manufacturability of the structure; however, it is a highly challenging constraint to treat and has been under debate in recent research in the same area. To fulfill design guidelines with respect to symmetry, balance, contiguity, disorientation and percentage rule of the layup, a reference for the stacking sequences (stacking sequence table or SST) is generated first. Then, an innovative fully gradient-based optimization approach in relation to a specific SST is introduced to obtain the optimum thickness distribution all over the structure while blending is fulfilled. The proposed optimization approach aims to turn the discrete optimization problem associated with the integer number of plies into a continuous one. As a result of a wing box deflection, a rib is subjected to load values which vary nonlinearly with the amount of deflection. The bending stiffness of a skin affects the wing box deflection and thus affects the load applied to a rib. This indicates the necessity of a coupled skin-rib optimization approach for a more realistic optimized design. The proposed method is examined with the optimization of the layup of a composite stiffened skin and rib of a wing torsion box subjected to in-plane normal and shear loads. Results show that the method can successfully prescribe a valid design with a significantly cheap computation cost.

Keywords: blending, buckling optimization, composite panels, wing torsion box

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1170 Structural Characterization of TIR Domains Interaction

Authors: Sara Przetocka, Krzysztof Żak, Grzegorz Dubin, Tadeusz Holak

Abstract:

Toll-like receptors (TLRs) play central role in the innate immune response and inflammation by recognizing pathogen-associated molecular patterns (PAMPs). A fundamental basis of TLR signalling is dependent upon the recruitment and association of adaptor molecules that contain the structurally conserved Toll/interleukin-1 receptor (TIR) domain. MyD88 (myeloid differentiation primary response gene 88) is the universal adaptor for TLRs and cooperates with Mal (MyD88 adapter-like protein, also known as TIRAP) in TLR4 response which is predominantly used in inflammation, host defence and carcinogenesis. Up to date two possible models of MyD88, Mal and TLR4 interactions have been proposed. The aim of our studies is to confirm or abolish presented models and accomplish the full structural characterisation of TIR domains interaction. Using molecular cloning methods we obtained several construct of MyD88 and Mal TIR domain with GST or 6xHis tag. Gel filtration method as well as pull-down analysis confirmed that recombinant TIR domains from MyD88 and Mal are binding in complexes. To examine whether obtained complexes are homo- or heterodimers we carried out cross-linking reaction of TIR domains with BS3 compound combined with mass spectrometry. To investigate which amino acid residues are involved in this interaction the NMR titration experiments were performed. 15N MyD88-TIR solution was complemented with non-labelled Mal-TIR. The results undoubtedly indicate that MyD88-TIR interact with Mal-TIR. Moreover 2D spectra demonstrated that simultaneously Mal-TIR self-dimerization occurs which is necessary to create proper scaffold for Mal-TIR and MyD88-TIR interaction. Final step of this study will be crystallization of MyD88 and Mal TIR domains complex. This crystal structure and characterisation of its interface will have an impact in understanding the TLR signalling pathway and possibly will be used in development of new anti-cancer treatment.

Keywords: cancer, MyD88, TIR domains, Toll-like receptors

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1169 Physicochemical Properties and Toxicity Studies on a Lectin from the Bulb of Dioscorea bulbifera

Authors: Uchenna Nkiruka Umeononihu, Adenike Kuku, Oludele Odekanyin, Olubunmi Babalola, Femi Agboola, Rapheal Okonji

Abstract:

In this study, a lectin from the bulb of Dioscorea bulbifera was purified, characterised, and its acute and sub-acute toxicity was investigated with a view to evaluate its toxic effects in mice. The protein from the bulb was extracted by homogenising 50 g of the bulb in 500 ml of phosphate buffered saline (0.025 M) of pH 7.2, stirred for 3 hr, and centrifuged at the speed of 3000 rpm. Blood group and sugar specificity assays of the crude extract were determined. The lectin was purified in a two-step procedure- gel filtration on Sephadex G-75 and affinity chromatography on Sepharose 4-B arabinose. The degree of purity of the purified lectin was ascertained by SDS-polyacrylamide gel electrophoresis. Detection of covalently bound carbohydrate was carried out with Periodic Acid-Schiffs (PAS) reagent staining technique. Effects of temperature, pH, and EDTA on the lectin were carried out using standard methods. This was followed by acute toxicity studies via oral and subcutaneous routes using mice. The animals were monitored for mortality and signs of toxicity. The sub-acute toxicity studies were carried out using rats. Different concentrations of the lectin were administered twice daily for 5 days via the subcutaneous route. The animals were sacrificed on the sixth day; blood samples and liver tissues were collected. Biochemical assays (determination of total protein, direct bilirubin, Alanine aminotransferase (ALT), Aspartate aminotransferase (AST), catalase (CAT), and superoxide dismutase (SOD)) were carried out on the serum and liver homogenates. The collected organs (heart, liver, kidney, and spleen) were subjected to histopathological analysis. The results showed that lectin from the bulbs of Dioscorea bulbifera agglutinated non-specifically the erythrocytes of the human ABO system as well as rabbit erythrocytes. The haemagglutinating activity was strongly inhibited by arabinose and dulcitol with minimum inhibitory concentrations of 0.781 and 6.25, respectively. The lectin was purified to homogeneity with native and subunit molecular weights of 56,273 and 29,373 Daltons, respectively. The lectin was thermostable up to 30 0C and lost 25 %, 33.3 %, and 100 % of its heamagglutinating activity at 40°C, 50°C, and 60°C, respectively. The lectin was maximally active at pH 4 and 5 but lost its total activity at pH eight, while EDTA (10 mM) had no effect on its haemagglutinating activity. PAS reagent staining showed that the lectin was not a glycoprotein. The sub-acute studies on rats showed elevated levels of ALT, AST, serum bilirubin, total protein in serum and liver homogenates suggesting damage to liver and spleen. The study concluded that the aerial bulb of D. bulbifera lectin was non-specific in its heamagglutinating activity and dimeric in its structure. The lectin shared some physicochemical characteristics with lectins from other Dioscorecea species and was moderately toxic to the liver and spleen of treated animals.

Keywords: Dioscorea bulbifera, heamagglutinin, lectin, toxicity

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1168 Bifurcations of a System of Rotor-Ball Bearings with Waviness and Squeeze Film Dampers

Authors: Sina Modares Ahmadi, Mohamad Reza Ghazavi, Mandana Sheikhzad

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Squeeze film damper systems (SFD) are often used in machines with high rotational speed to reduce non-periodic behavior by creating external damping. These types of systems are frequently used in aircraft gas turbine engines. There are some structural parameters which are of great importance in designing these kinds of systems, such as oil film thickness, C, and outer race mass, mo. Moreover, there is a crucial parameter associated with manufacturing process, under the title of waviness. Geometric imperfections are often called waviness if its wavelength is much longer than Hertzian contact width which is a considerable source of vibration in ball bearings. In this paper, a system of a flexible rotor and two ball bearings with floating ring squeeze film dampers and consideration of waviness has been modeled and solved by a numerical integration method, namely Runge-Kutta method to investigate the dynamic response of the system. The results show that by increasing the number of wave lobes, which is due to inappropriate manufacturing, non- periodic and chaotic behavior increases. This result reveals the importance of manufacturing accuracy. Moreover, as long as C< 1.5×10-4 m, by increasing the oil film thickness, unwanted vibrations and non-periodic behavior of the system have been reduced, On the other hand, when C>1.5×10-4 m, increasing the outer oil film thickness results in the increasing chaotic and non-periodic responses. This result shows that although the presence of oil film results in reduction the non-periodic and chaotic behaviors, but the oil film has an optimal thickness. In addition, with increasing mo, the disc displacement amplitude increases. This result reveals the importance of utilizing light materials in manufacturing the squeeze film dampers.

Keywords: squeeze-film damper, waviness, ball bearing, bifurcation

Procedia PDF Downloads 375
1167 Effect of 12 Weeks Pedometer-Based Workplace Program on Inflammation and Arterial Stiffness in Young Men with Cardiovascular Risks

Authors: Norsuhana Omar, Amilia Aminuddina Zaiton Zakaria, Raifana Rosa Mohamad Sattar, Kalaivani Chellappan, Mohd Alauddin Mohd Ali, Norizam Salamt, Zanariyah Asmawi, Norliza Saari, Aini Farzana Zulkefli, Nor Anita Megat Mohd. Nordin

Abstract:

Inflammation plays an important role in the pathogenesis of vascular dysfunction leading to arterial stiffness. Pulse wave velocity (PWV) and augmentation index (AS), as tools for the assessment of vascular damages are widely used and have been shown to predict cardiovascular disease (CVD). C-reactive protein (CRP) is a marker of inflammation. Several studies noted that regular exercise is associated with reduced arterial stiffness. The lack of exercise among Malaysians and the increasing CVD morbidity and mortality among young men are of concern. In Malaysia data on the workplace exercise intervention is scarce. A programme was designed to enable subjects to increase their level of walking as part of their daily work routine and self-monitored by using pedometers. The aim of this study to evaluate the reducing of inflammation by measuring CRP and improvement arterial stiffness measured by carotid femoral PWV (PWVCF) and AI. A total of 70 young men (20 - 40 years) who were sedentary, achieving less than 5,000 steps/day in casual walking with 2 or more cardiovascular risk factors were recruited in Institute of Vocational Skills for Youth (IKBN Hulu Langat). Subjects were randomly assigned to a control (CG) (n=34; no change in walking) and pedometer group (PG) (n=36; minimum target: 8,000 steps/day). The CRP was measured by using immunological method while PWVCF and AI were measured using Vicorder. All parameters were measured at baseline and after 12 weeks. Data for analysis was conducted using Statistical Package of Social Sciences Version 22 (SPSS Inc., Chicago, IL, USA). At post intervention, the CG step counts were similar (4983 ± 366vs 5697 ± 407steps/day). The PG increased step count from 4996 ± 805 to 10,128 ±511 steps/day (P<0.001). The PG showed significant improvement in anthropometric variables and lipid (time and group effect p<0.001). For vascular assessment, the PG showed significantly decreased for time and effect (p<0.001) for PWV (7.21± 0.83 to 6.42 ± 0.89) m/s; AI (11.88± 6.25 to 8.83 ± 3.7) % and CRP (pre= 2.28 ± 3.09, post=1.08± 1.37mg/L). However, no changes were seen in CG. As a conclusion, a pedometer-based walking programme may be an effective strategy for promoting increased daily physical activity which reduces cardiovascular risk markers and thus improve cardiovascular health in terms of inflammation and arterial stiffness. The community intervention for health maintenance has potential to adopt walking as an exercise and adopting vascular fitness index as the performance measuring tools.

Keywords: arterial stiffness, exercise, inflammation, pedometer

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1166 Effects of the Air Supply Outlets Geometry on Human Comfort inside Living Rooms: CFD vs. ADPI

Authors: Taher M. Abou-deif, Esmail M. El-Bialy, Essam E. Khalil

Abstract:

The paper is devoted to numerically investigating the influence of the air supply outlets geometry on human comfort inside living looms. A computational fluid dynamics model is developed to examine the air flow characteristics of a room with different supply air diffusers. The work focuses on air flow patterns, thermal behavior in the room with few number of occupants. As an input to the full-scale 3-D room model, a 2-D air supply diffuser model that supplies direction and magnitude of air flow into the room is developed. Air distribution effect on thermal comfort parameters was investigated depending on changing the air supply diffusers type, angles and velocity. Air supply diffusers locations and numbers were also investigated. The pre-processor Gambit is used to create the geometric model with parametric features. Commercially available simulation software “Fluent 6.3” is incorporated to solve the differential equations governing the conservation of mass, three momentum and energy in the processing of air flow distribution. Turbulence effects of the flow are represented by the well-developed two equation turbulence model. In this work, the so-called standard k-ε turbulence model, one of the most widespread turbulence models for industrial applications, was utilized. Basic parameters included in this work are air dry bulb temperature, air velocity, relative humidity and turbulence parameters are used for numerical predictions of indoor air distribution and thermal comfort. The thermal comfort predictions through this work were based on ADPI (Air Diffusion Performance Index),the PMV (Predicted Mean Vote) model and the PPD (Percentage People Dissatisfied) model, the PMV and PPD were estimated using Fanger’s model.

Keywords: thermal comfort, Fanger's model, ADPI, energy effeciency

Procedia PDF Downloads 404