Search results for: functional random differential equation
Commenced in January 2007
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Search results for: functional random differential equation

1644 Study of the Adsorptives Properties of Zeolites X Exchanged by the Cations Cu2 + and/or Zn2+

Authors: H. Hammoudi, S. Bendenia, I. Batonneau-Gener, A. Khelifa

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Applying growing zeolites is due to their intrinsic physicochemical properties: a porous structure, regular, generating a large free volume, a high specific surface area, acidic properties of interest to the origin of their activity, selectivity energy and dimensional, leading to a screening phenomenon, hence the name of molecular sieves is generally attributed to them. Most of the special properties of zeolites have been valued as direct applications such as ion exchange, adsorption, separation and catalysis. Due to their crystalline structure stable, their large pore volume and their high content of cation X zeolites are widely used in the process of adsorption and separation. The acidic properties of zeolites X and interesting selectivity conferred on them their porous structure is also have potential catalysts. The study presented in this manuscript is devoted to the chemical modification of an X zeolite by cation exchange. Ion exchange of zeolite NaX by Zn 2 + cations and / or Cu 2 + is gradually conducted by following the evolution of some of its characteristics: crystallinity by XRD, micropore volume by nitrogen adsorption. Once characterized, the different samples will be used for the adsorption of propane and propylene. Particular attention is paid thereafter, on the modeling of adsorption isotherms. In this vein, various equations of adsorption isotherms and localized mobile, some taking into account the adsorbate-adsorbate interactions, are used to describe the experimental isotherms. We also used the Toth equation, a mathematical model with three parameters whose adjustment requires nonlinear regression. The last part is dedicated to the study of acid properties of Cu (x) X, Zn (x) X and CuZn (x) X, with the adsorption-desorption of pyridine followed by IR. The effect of substitution at different rates of Na + by Cu2 + cations and / or Zn 2 +, on the crystallinity and on the textural properties was treated. Some results on the morphology of the crystallites and the thermal effects during a temperature rise, obtained by scanning electron microscopy and DTA-TGA thermal analyzer, respectively, are also reported. The acidity of our different samples was also studied. Thus, the nature and strength of each type of acidity are estimated. The evaluation of these various features will provide a comparison between Cu (x) X, Zn (x) X and CuZn (x) X. One study on adsorption of C3H8 and C3H6 in NaX, Cu (x) X , Zn (x) x and CuZn (x) x has been undertaken.

Keywords: adsorption, acidity, ion exchange, zeolite

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1643 Effect of Different Porous Media Models on Drug Delivery to Solid Tumors: Mathematical Approach

Authors: Mostafa Sefidgar, Sohrab Zendehboudi, Hossein Bazmara, Madjid Soltani

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Based on findings from clinical applications, most drug treatments fail to eliminate malignant tumors completely even though drug delivery through systemic administration may inhibit their growth. Therefore, better understanding of tumor formation is crucial in developing more effective therapeutics. For this purpose, nowadays, solid tumor modeling and simulation results are used to predict how therapeutic drugs are transported to tumor cells by blood flow through capillaries and tissues. A solid tumor is investigated as a porous media for fluid flow simulation. Most of the studies use Darcy model for porous media. In Darcy model, the fluid friction is neglected and a few simplified assumptions are implemented. In this study, the effect of these assumptions is studied by considering Brinkman model. A multi scale mathematical method which calculates fluid flow to a solid tumor is used in this study to investigate how neglecting fluid friction affects the solid tumor simulation. In this work, the mathematical model in our previous studies is developed by considering two model of momentum equation for porous media: Darcy and Brinkman. The mathematical method involves processes such as fluid flow through solid tumor as porous media, extravasation of blood flow from vessels, blood flow through vessels and solute diffusion, convective transport in extracellular matrix. The sprouting angiogenesis model is used for generating capillary network and then fluid flow governing equations are implemented to calculate blood flow through the tumor-induced capillary network. Finally, the two models of porous media are used for modeling fluid flow in normal and tumor tissues in three different shapes of tumors. Simulations of interstitial fluid transport in a solid tumor demonstrate that the simplifications used in Darcy model affect the interstitial velocity and Brinkman model predicts a lower value for interstitial velocity than the values that Darcy model does.

Keywords: solid tumor, porous media, Darcy model, Brinkman model, drug delivery

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1642 Anthropometric and Physical Fitness Ability Profile of Elite and Non-Elite Boxers of Manipur

Authors: Anthropometric, Physical Fitness Ability Profile of Elite, Non-Elite Boxers of Manipur

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Background: Boxing is one of the oldest combat sports where different anthropological and fitness ability parameters determine performance. It is characterized by short duration, high intensity bursts of activity. The purpose of this research was to determine anthropometric and physical fitness profile of male elite and non-elite boxers of Manipur and to compare the two groups. Materials and Methods: Nineteen subjects were selected as elite boxers and twenty-four were non-elite boxers of Manipur. A cross-sectional study was conducted on anthropometric measurements and physical fitness ability tests on 33 subjects (elite and non-elite boxers). Statistical analysis was done using descriptive statistics, t-test and logistic regression with the help of SPSS version 15 software. Results: Results showed elite boxers have significantly reduced neck girth and calf girth as compare to non-elite boxers. Elite boxers have significantly lower sub scapular skin fold (SSF) and supra iliac skin fold (SISF) than their counterparts. Higher stature, larger BTB and lower percent fat are associated with higher performance in boxing. Sit ups (SU), standing Broad Jump (SBJ), Plat taping (PT), Sit and reach (SAR) and Harvard Step Test (HST) are predicted as most contributing factors enhancing performance level among the physical fitness components. Elite boxers are found to have more functional strength (sit ups), higher explosive strength (SBJ), more agility (PT), cardio-vascular endurance and flexibility (SAR) than non-elite boxers. Conclusion: In conclusion, lower fat, higher lean body mass, larger bi-trochantric breadth, high explosive strength, agility and flexibility are significantly associated with higher performance and chance of becoming elite boxers.

Keywords: anthropometry, elite and non-elite boxers, Manipur, physical fitness

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1641 Computer Self-Efficacy, Study Behaviour and Use of Electronic Information Resources in Selected Polytechnics in Ogun State, Nigeria

Authors: Fredrick Olatunji Ajegbomogun, Bello Modinat Morenikeji, Okorie Nancy Chituru

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Electronic information resources are highly relevant to students' academic and research needs but are grossly underutilized, despite the institutional commitment to making them available. The under-utilisation of these resources could be attributed to a low level of study behaviour coupled with a low level of computer self-efficacy. This study assessed computer self-efficacy, study behaviour, and the use of electronic information resources by students in selected polytechnics in Ogun State. A simple random sampling technique using Krejcie and Morgan's (1970) Table was used to select 370 respondents for the study. A structured questionnaire was used to collect data on respondents. Data were analysed using frequency counts, percentages, mean, standard deviation, Pearson Product Moment Correlation (PPMC) and multiple regression analysis. Results reveal that the internet (= 1.94), YouTube (= 1.74), and search engines (= 1.72) were the common information resources available to the students, while the Internet (= 4.22) is the most utilized resource. Major reasons for using electronic information resources were to source materials and information (= 3.30), for research (= 3.25), and to augment class notes (= 2.90). The majority (91.0%) of the respondents have a high level of computer self-efficacy in the use of electronic information resources through selecting from screen menus (= 3.12), using data files ( = 3.10), and efficient use of computers (= 3.06). Good preparation for tests (= 3.27), examinations (= 3.26), and organization of tutorials (= 3.11) are the common study behaviours of the respondents. Overall, 93.8% have good study behaviour. Inadequate computer facilities to access information (= 3.23), and poor internet access (= 2.87) were the major challenges confronting students’ use of electronic information resources. According to the PPMC results, study behavior (r = 0.280) and computer self-efficacy (r = 0.304) have significant (p 0.05) relationships with the use of electronic information resources. Regression results reveal that self-efficacy (=0.214) and study behavior (=0.122) positively (p 0.05) influenced students' use of electronic information resources. The study concluded that students' use of electronic information resources depends on the purpose, their computer self-efficacy, and their study behaviour. Therefore, the study recommended that the management should encourage the students to improve their study habits and computer skills, as this will enhance their continuous and more effective utilization of electronic information resources.

Keywords: computer self-efficacy, study behaviour, electronic information resources, polytechnics, Nigeria

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1640 Impact of Information and Communication Technology on Academic Performance of Senior Secondary Schools Students in Gwagwalada Area Council of Federal Capital Territory, Abuja

Authors: Suleiman Garba, Haruna Ishaku

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Information and communication technology (ICT) includes any communication device encompassing: radio, television, cellular phones, computer, satellite systems and so on, as well as the various services and applications associated with them. The significance of ICT cannot be over-emphasized in education. The teaching and learning processes have integrated with the application of ICTs for effectiveness and enhancement of academic performance among the students. Today, as the educational sector is faced with series of changes and reforms, it was noted that the problem of information technology illiteracy was a serious one among the schools’ teachers in the country as it cuts across primary, secondary schools and tertiary institutions. This study investigated the impact of ICT on the academic performance of senior secondary schools students in Gwagwalada Area Council of Federal Capital Territory (FCT), Abuja. A sample of 120 SSS III students was involved in the study. They were selected by using simple random sampling technique. A questionnaire was developed and validated through expert judgement and reliability co-efficient of 0.81 was obtained. It was used to gather relevant data from the respondents. Findings revealed that there was positive impact of ICT on academic performance of senior secondary schools students. The findings indicated the causes of poor academic performance among the students as lack of qualified teachers to teach in schools, peer group influence, and bullying. Significantly, the findings revealed that ICT had a positive impact on students’ academic performance. The null hypotheses were tested using t-test at 0.05 level of significance. It was discovered that there was significant difference between male and female secondary schools’ students' impact of ICT on academic performance in Gwagawalada Area Council of FCT-Abuja. Based on these findings, some recommendations were made which include: adequate funds should be provided towards procurement of ICT resources, relevant textbooks to enhance students’ active participation in learning processes and students should be provided with internet accessibility at inexpensive rate so as to create a platform for accessing useful information in the pursuit of academic excellence.

Keywords: academic performance, impact, information communication technology, schools, students

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1639 Characterization and Modelling of Aerosol Droplet in Absorption Columns

Authors: Hammad Majeed, Hanna Knuutila, Magne Hillestad, Hallvard F. Svendsen

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Formation of aerosols can cause serious complications in industrial exhaust gas CO2 capture processes. SO3 present in the flue gas can cause aerosol formation in an absorption based capture process. Small mist droplets and fog formed can normally not be removed in conventional demisting equipment because their submicron size allows the particles or droplets to follow the gas flow. As a consequence of this aerosol based emissions in the order of grams per Nm3 have been identified from PCCC plants. In absorption processes aerosols are generated by spontaneous condensation or desublimation processes in supersaturated gas phases. Undesired aerosol development may lead to amine emissions many times larger than what would be encountered in a mist free gas phase in PCCC development. It is thus of crucial importance to understand the formation and build-up of these aerosols in order to mitigate the problem. Rigorous modelling of aerosol dynamics leads to a system of partial differential equations. In order to understand mechanics of a particle entering an absorber an implementation of the model is created in Matlab. The model predicts the droplet size, the droplet internal variable profiles and the mass transfer fluxes as function of position in the absorber. The Matlab model is based on a subclass method of weighted residuals for boundary value problems named, orthogonal collocation method. The model comprises a set of mass transfer equations for transferring components and the essential diffusion reaction equations to describe the droplet internal profiles for all relevant constituents. Also included is heat transfer across the interface and inside the droplet. This paper presents results describing the basic simulation tool for the characterization of aerosols formed in CO2 absorption columns and gives examples as to how various entering droplets grow or shrink through an absorber and how their composition changes with respect to time. Below are given some preliminary simulation results for an aerosol droplet composition and temperature profiles.

Keywords: absorption columns, aerosol formation, amine emissions, internal droplet profiles, monoethanolamine (MEA), post combustion CO2 capture, simulation

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1638 Genomics Approach for Excavation of NAS Genes from Nutri Rich Minor Millet Crops: Transforming Perspective from Orphan Plants to Future Food Crops

Authors: Mahima Dubey, Girish Chandel

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Minor millets are highly nutritious and climate resilient cereal crops. These features make them ideal candidates to excavate the physiology of the underlying mechanism. In an attempt to understand the basis of mineral nutrition in minor millets, a set of five Barnyard millet genotypes were analyzed for grain Fe and Zn content under contrasting Fe-Zn supply to identify genotypes proficient in tolerating mineral deficiency. This resulted in the identification of Melghat-1 genotype to be nutritionally superior with better ability to withstand deficiency. Expression analysis of several Nicotianamine synthase (NAS) genes showed that HvNAS1 and OsNAS2 genes were prominent in positively mediating mineral deficiency response in Barnyard millet. Further, strategic efforts were employed for fast-track identification of more effective orthologous NAS genes from Barnyard millet. This resulted in the identification of two genes namely EfNAS1 (orthologous to HvNAS1 of barley) and EfNAS2 (orthologous to OsNAS2 gene of rice). Sequencing and thorough characterization of these sequences revealed the presence of intact NAS domain and signature tyrosine and di-leucine motifs in their predicted proteins and thus established their candidature as functional NAS genes in Barnyard millet. Moreover, EfNAS1 showed structural superiority over previously known NAS genes and is anticipated to have role in more efficient metal transport. Findings of the study provide insight into Fe-Zn deficiency response and mineral nutrition in millets. This provides millets with a physiological edge over micronutrient deficient staple cereals such as rice in withstanding Fe-Zn deficiency and subsequently accumulating higher levels of Fe and Zn in millet grains.

Keywords: gene expression, micronutrient, millet, ortholog

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1637 Epidemiology of Toxoplasma gondii Infection in Animals of the Arabian Peninsula: A Systematic Review and Meta-Analysis

Authors: Ebtisam A. Al-Mslemani, Khalid A. Enan, Asmaa Abdelgadier, Nada Assaad, Zaynab Elhussein, Khalid Eltom

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Background: Toxoplasma gondii (T. gondii) is a zoonotic parasite that can be transmitted from animals to humans, with felids acting as its definitive host. Thus, understanding the epidemiology of this parasite in animal populations is vital to controlling its transmission to humans as well as to other animal groups. Objectives: This systematic review and meta-analysis aim to summarise and analyse reports of T. gondii infection in animal species residing in the Arabian Peninsula. Methods: It was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), with relevant studies being retrieved from MEDLINE/PubMed, Scopus, Cochrane Library, Google Scholar and ScienceDirect. All articles published in Arabic or English languages between January 2000 and December 2020 were screened for eligibility. The random effects model was used to calculate the pooled prevalence of T. gondii infection in different animal populations which were found to harbour this infection. The critical appraisal tool for prevalence studies designed by the Joanna Briggs Institute (JBI) was used to assess the risk of bias in all included studies. Results: A total of 15 studies were retrieved, reporting prevalence estimates from 4 countries in this region and in 13 animal species. A quantitative meta-analysis estimated a pooled prevalence of 43% in felids [95% confidence interval (CI) = 23-64%, I2 index = 100%], 48% in sheep (95% CI = 27-70%, I2 = 99%) and 21% in camels (95% CI = 7-35%, I2 = 99%). Evidence of possible publication bias was found in both felids and sheep. Conclusions: This meta-analysis estimates a high prevalence of T. gondii infection in animal species that are of high economic and cultural importance to countries of this region. Hence, these findings provide valuable insight to public health authorities as well as economic and animal resources advisors in countries of the Arabian Peninsula.

Keywords: Arabian Peninsula, toxoplasma gondii, animals; meta-analysis, toxoplasmosis

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1636 Assessing the Impact of Climate Change on Pulses Production in Khyber Pakhtunkhwa, Pakistan

Authors: Khuram Nawaz Sadozai, Rizwan Ahmad, Munawar Raza Kazmi, Awais Habib

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Climate change and crop production are intrinsically associated with each other. Therefore, this research study is designed to assess the impact of climate change on pulses production in Southern districts of Khyber Pakhtunkhwa (KP) Province of Pakistan. Two pulses (i.e. chickpea and mung bean) were selected for this research study with respect to climate change. Climatic variables such as temperature, humidity and precipitation along with pulses production and area under cultivation of pulses were encompassed as the major variables of this study. Secondary data of climatic variables and crop variables for the period of thirty four years (1986-2020) were obtained from Pakistan Metrological Department and Agriculture Statistics of KP respectively. Panel data set of chickpea and mung bean crops was estimated separately. The analysis validate that both data sets were a balanced panel data. The Hausman specification test was run separately for both the panel data sets whose findings had suggested the fixed effect model can be deemed as an appropriate model for chickpea panel data, however random effect model was appropriate for estimation of the panel data of mung bean. Major findings confirm that maximum temperature is statistically significant for the chickpea yield. This implies if maximum temperature increases by 1 0C, it can enhance the chickpea yield by 0.0463 units. However, the impact of precipitation was reported insignificant. Furthermore, the humidity was statistically significant and has a positive association with chickpea yield. In case of mung bean the minimum temperature was significantly contributing in the yield of mung bean. This study concludes that temperature and humidity can significantly contribute to enhance the pulses yield. It is recommended that capacity building of pulses growers may be made to adapt the climate change strategies. Moreover, government may ensure the availability of climate change resistant varieties of pulses to encourage the pulses cultivation.

Keywords: climate change, pulses productivity, agriculture, Pakistan

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1635 In-Depth Analysis on Sequence Evolution and Molecular Interaction of Influenza Receptors (Hemagglutinin and Neuraminidase)

Authors: Dong Tran, Thanh Dac Van, Ly Le

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Hemagglutinin (HA) and Neuraminidase (NA) play an important role in host immune evasion across influenza virus evolution process. The correlation between HA and NA evolution in respect to epitopic evolution and drug interaction has yet to be investigated. In this study, combining of sequence to structure evolution and statistical analysis on epitopic/binding site specificity, we identified potential therapeutic features of HA and NA that show specific antibody binding site of HA and specific binding distribution within NA active site of current inhibitors. Our approach introduces the use of sequence variation and molecular interaction to provide an effective strategy in establishing experimental based distributed representations of protein-protein/ligand complexes. The most important advantage of our method is that it does not require complete dataset of complexes but rather directly inferring feature interaction from sequence variation and molecular interaction. Using correlated sequence analysis, we additionally identified co-evolved mutations associated with maintaining HA/NA structural and functional variability toward immunity and therapeutic treatment. Our investigation on the HA binding specificity revealed unique conserved stalk domain interacts with unique loop domain of universal antibodies (CR9114, CT149, CR8043, CR8020, F16v3, CR6261, F10). On the other hand, NA inhibitors (Oseltamivir, Zaninamivir, Laninamivir) showed specific conserved residue contribution and similar to that of NA substrate (sialic acid) which can be exploited for drug design. Our study provides an important insight into rational design and identification of novel therapeutics targeting universally recognized feature of influenza HA/NA.

Keywords: influenza virus, hemagglutinin (HA), neuraminidase (NA), sequence evolution

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1634 Manipulating The PAAR Proteins of Acinetobacter Baumannii

Authors: Irene Alevizos, Jessica Lewis, Marina Harper, John Boyce

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Acinetobacter baumannii causes a range of severe nosocomial-acquired infections, and many strains are multi-drug resistant. A. baumannii possesses survival mechanisms allowing it to thrive in competitive polymicrobial environments, including a Type VI Secretion System (T6SS) that injects effector proteins into other bacteria to give a competitive advantage. The effects of T6SS firing are broad and depend entirely on the effector that is delivered. Effects can include toxicity against prokaryotic or eukaryotic cells and the acquisition of essential nutrients. The T6SS of some species can deliver ‘specialised effectors’ that are fused directly to T6SS components, such as PAAR proteins. PAAR proteins are predicted to form the piercing tip of the T6SS and are essential for T6SS function. Although no specialised effectors have been identified in A. baumannii, many strains encode multiple PAAR proteins. Analysis of PAAR proteins across the species identified 12 families of PAAR proteins with distinct C-terminal extensions. A. baumannii AB307-0294 encodes two PAAR proteins, one of which has a C-terminal extension. Mutation of one or both of the PAAR-encoding genes in this strain showed that expression of either PAAR protein was sufficient for T6SS function. We employed a heterologous expression approach and determined that PAAR proteins from different A. baumannii strains, as well as the closely related A. baylyi species, could complement the A. baumannii ∆paar mutant and restore T6SS function. Furthermore, we showed that PAAR fusions could be used to deliver artificially cloned protein fragments by generating Histidine- and Streptavidin- tagged PAAR specialised effectors, which restored T6SS activity. This provides evidence that the fusion of protein fragments onto PAAR proteins in A. baumannii is compatible with a functional T6SS. Successful delivery by this mechanism extends the scope of what the T6SS can deliver, including user designed proteins.

Keywords: A. baumannii, effectors, PAAR, T6SS

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1633 Selective Fermentations of Monosaccharides by Osmotolerant Yeast Cultures

Authors: Elizabeth Loza-Valerdi, Victor Pardiñas-Rios, Arnulfo Pluma-Pluma, Andres Breton-Toral, Julio Cercado-Jaramillo

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The purification processes for mixtures of isomeric monosaccharides using industrial chromatographic methods poses a serious technical challenge. Mixtures of 2 or 3 monosaccharides are difficult to separate by strictly physical or chemical techniques. Differential fermentation by microbial cultures is an increasingly interesting way of selective enrichment in a particular kind of monosaccharides when a mixture of them is present in the solution, and only one has economical value. Osmotolerant yeast cultures provide an interesting source of biocatalysts for the selective catabolism of monosaccharides in media containing high concentrations of total soluble sugars. A collection of 398 yeast strains has been obtained using endemic and unique sources of fruit juices, industrial syrups, honey, and other high sugar content substrates, either natural or man made, products and by-products from Mexico. The osmotolerance of the strains was assessed by plate assay both in glucose (20-40-60%w/w). Strains were classified according to their osmotolerance in low, medium or highly tolerant to high glucose concentrations. The purified cultures were tested by their ability to growth in a solid plate media or liquid media of Yeas Nitrogen Base (YNB), added with specific monosaccharides as sole carbon source (glucose, galactose, lactose and fructose). Selected strains were subsequently tested in fermentation experiments with mixtures of two monosaccharides (galactose/glucose and glucose/fructose). Their ability to grow and selectively catabolize one monosaccharide was evaluated. Growth, fermentation activity and products of metabolism were determined by plate counts, CO2 production, turbidity and chromatographic analysis by HPLC. Selective catabolism of one monosaccharide in liquid media containing two monosaccharides was confirmed for 8 strains. Ion Exchange chromatographic processes were used in production of high fructose or galactose syrup. Laboratory scale processes for the production of fructose or galactose enriched syrups is now feasible, with important applications in food (like high fructose syrup as edulcorant) and fermentation technology (for GOS production).

Keywords: osmotolerant yeasts, selective metabolism, fructose syrup, GOS

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1632 Nonlinear Response of Infinite Beams on a Multilayer Tensionless Extensible Geosynthetic – Reinforced Earth Bed under Moving Load

Authors: K. Karuppasamy

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In this paper analysis of an infinite beam resting on multilayer tensionless extensible geosynthetic reinforced granular fill - poor soil system overlying soft soil strata under moving the load with constant velocity is presented. The beam is subjected to a concentrated load moving with constant velocity. The upper reinforced granular bed is modeled by a rough membrane embedded in Pasternak shear layer overlying a series of compressible nonlinear Winkler springs representing the underlying the very poor soil. The multilayer tensionless extensible geosynthetic layer has been assumed to deform such that at the interface the geosynthetic and the soil have some deformation. Nonlinear behavior of granular fill and the very poor soil has been considered in the analysis by means of hyperbolic constitutive relationships. Governing differential equations of the soil foundation system have been obtained and solved with the help of appropriate boundary conditions. The solution has been obtained by employing finite difference method by means of Gauss-Siedel iterative scheme. Detailed parametric study has been conducted to study the influence of various parameters on the response of soil – foundation system under consideration by means of deflection and bending moment in the beam and tension mobilized in the geosynthetic layer. These parameters include the magnitude of applied load, the velocity of the load, damping, the ultimate resistance of the poor soil and granular fill layer. The range of values of parameters has been considered as per Indian Railways conditions. This study clearly observed that the comparisons of multilayer tensionless extensible geosynthetic reinforcement with poor foundation soil and magnitude of applied load, relative compressibility of granular fill and ultimate resistance of poor soil has significant influence on the response of soil – foundation system. However, for the considered range of velocity, the response has been found to be insensitive towards velocity. The ultimate resistance of granular fill layer has also been found to have no significant influence on the response of the system.

Keywords: infinite beams, multilayer tensionless extensible geosynthetic, granular layer, moving load and nonlinear behavior of poor soil

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1631 Layer-By-Layer Deposition of Poly(Ethylene Imine) Nanolayers on Polypropylene Nonwoven Fabric: Electrostatic and Thermal Properties

Authors: Dawid Stawski, Silviya Halacheva, Dorota Zielińska

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The surface properties of many materials can be readily and predictably modified by the controlled deposition of thin layers containing appropriate functional groups and this research area is now a subject of widespread interest. The layer-by-layer (lbl) method involves depositing oppositely charged layers of polyelectrolytes onto the substrate material which are stabilized due to strong electrostatic forces between adjacent layers. This type of modification affords products that combine the properties of the original material with the superficial parameters of the new external layers. Through an appropriate selection of the deposited layers, the surface properties can be precisely controlled and readily adjusted in order to meet the requirements of the intended application. In the presented paper a variety of anionic (poly(acrylic acid)) and cationic (linear poly(ethylene imine), polymers were successfully deposited onto the polypropylene nonwoven using the lbl technique. The chemical structure of the surface before and after modification was confirmed by reflectance FTIR spectroscopy, volumetric analysis and selective dyeing tests. As a direct result of this work, new materials with greatly improved properties have been produced. For example, following a modification process significant changes in the electrostatic activity of a range of novel nanocomposite materials were observed. The deposition of polyelectrolyte nanolayers was found to strongly accelerate the loss of electrostatically generated charges and to increase considerably the thermal resistance properties of the modified fabric (the difference in T50% is over 20°C). From our results, a clear relationship between the type of polyelectrolyte layer deposited onto the flat fabric surface and the properties of the modified fabric was identified.

Keywords: layer-by-layer technique, polypropylene nonwoven, surface modification, surface properties

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1630 Socioeconomic Impacts of Innovative Housing Construction Technologies in Slum Upgrading: Case of Mathare Valley Nairobi, Kenya

Authors: Edmund M. Muthigani

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Background: Adequate, decent housing is a universal human right integral component. Resources’ costs and intensified rural-urban migration have increased the demand for affordable housing in urban areas. Modern knowledge-based economy uses innovation. The construction industry uses product and process innovation to provide adequate and decent low-cost housing. Kenya adopted innovation practices in slum upgrading that used cost-effectively locally available building materials. This study objectively looked at the outcomes, social and economic impacts of innovative housing technologies construction in the Mathare valley slums upgrading project. Methods: This post-occupancy study used an exploratory-descriptive research design. Random sampling was used to sample 384 users of low-cost housing projects in Mathare Valley, Nairobi County. Research instruments included semi-structured questionnaires and interview guides. Pilot study, validity and reliability tests ensured the quality of a study. Ethical considerations included university approval and consent. Statistical package for social sciences (SPSS) software version 21 was applied to compute the descriptive and inferential statistics. Findings: Slum-upgrading had a significant-positive outcome on improved houses and community. Social impacts included communal facilities, assurance of security of tenure, and retained frameworks of establishments. Economic impacts included employment; affordable and durable units (p values <0.05). The upgrading process didn’t influence rent fees, was corrupt and led to the displacement of residents. Conclusion: Slum upgrading process impacted positively. Similar projects should consider residents in decision-making.

Keywords: innovation, technologies, slum upgrading, Mathare valley slum, social impact, economic impact

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1629 Determination of Community Based Reference Interval of Aspartate Aminotransferase to Platelet Ratio Index (APRI) among Healthy Populations in Mekelle City Tigray, Northern Ethiopia

Authors: Getachew Belay Kassahun

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Background: Aspartate aminotransferase to Platelet Ratio Index (APRI) currently becomes a biomarker for screening liver fibrosis since liver biopsy procedure is invasive and variation in pathological interpretation. Clinical Laboratory Standard Institute recommends establishing age, sex and environment specific reference interval for biomarkers in a homogenous population. The current study was aimed to derive community based reference interval of APRI aged between 12 and 60 years old in Mekelle city Tigrai, Northern Ethiopia. Method: Six hundred eighty eight study participants were collected from three districts in Mekelle city. The 3 districts were selected through random sampling technique and sample size to kebelles (small administration) were distributed proportional to household number in each district. Lottery method was used at household level if more than 2 study participants to each age partition were found. A community based cross sectional in a total of 534 study participants, 264 male and 270 females, were included in the final laboratory and data analysis but around 154 study participants were excluded through exclusion criteria. Aspartate aminotransferase was analyzed through Biosystem chemistry analyzer and Sysmix machine was used to analyze platelet. Man Whitney U test non parametric stastical tool was used to appreciate stastical difference among gender after excluding the outliers through Box and Whisker. Result: The study appreciated stastical difference among gender for APRI reference interval. The combined, male and female reference interval in the current study was 0.098-0.390, 0.133-0.428 and 0.090-0.319 respectively. The upper and lower reference interval of males was higher than females in all age partition and there was no stastical difference (p-value (<0.05)) between age partition. Conclusion: The current study showed using sex specific reference interval is significant to APRI biomarker in clinical practice for result interpretation.

Keywords: reference interval, aspartate aminotransferase to platelet ratio Index, Ethiopia, tigray

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1628 Equipping Organic Farming in Medicinal and Aromatic Plants: Central Institute of Medicinal and Aromatic Plants' Scientific Interventions

Authors: Alok Kalra

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Consumers and practitioners (medical herbalists, pharmacists, and aromatherapists) with strong and increased awareness about health and environment demand organically grown medicinal and aromatic plants (MAPs) to offer a valued product. As the system does not permit the use of synthetic fertilizers the use of nutrient rich organic manures is extremely important. CSIR-CIMAP has developed a complete recycling package for managing distillation and agro-waste of medicinal and aromatic plants for production of superior quality vermicompost involving microbes capable of producing high amounts of humic acid. The major benefits being faster composting period and nutrient rich vermicompost; a nutrient advantage of about 100-150% over the most commonly used organic manure (FYM). At CSIR-CIMAP, strains of microbial inoculants with multiple activities especially strains useful both as biofertilizers and biofungicide and consortia of microbes possessing diverse functional activities have been developed. CSIR-CIMAP has also initiated a program where a large number of accessions are being screened for identifying organic proficient genotypes in mints, ashwagandha, geranium and safed musli. Some of the natural plant growth promoters like calliterpenones from the plant Callicarpa macrophylla has been tested successfully for induction of rooting in stem cuttings and improving growth and yield of various crops. Some of the microbes especially the endophytes have even been identified improving the active constituents of medicinal and aromatic plants. The above said scientific interventions making organic farming a charming proposition would be discussed in details.

Keywords: organic agriculture, microbial inoculants, organic fertilizers, natural plant growth promoters

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1627 Absorption Kinetic and Tensile Mechanical Properties of Swollen Elastomer/Carbon Black Nanocomposites using Typical Solvents

Authors: F. Elhaouzi, H. Lahlali, M. Zaghrioui, I. El Aboudi A. BelfKira, A. Mdarhri

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The effect of physico chemical properties of solvents on the transport process and mechanical properties in elastomeric nano composite materials is reported. The investigated samples are formed by a semi-crystalline ethylene-co-butyl acrylate polymer filled with hard spherical carbon black (CB) nano particles. The swelling behavior was studied by immersion the dried samples in selected solvents at room temperature during 2 days. For this purpose, two chemical compounds methyl derivatives of aromatic hydrocarbons of benzene, i.e. toluene and xylene, are used to search for the mass and molar volume dependence on the absorption kinetics. Mass gain relative to the mass of dry material at specific times was recorded to probe the absorption kinetics. The transport of solvent molecules in these filled elastomeric composites is following a Fickian diffusion mechanism. Additionally, the swelling ratio and diffusivity coefficient deduced from the Fickian law are found to decrease with the CB concentration. These results indicate that the CB nano particles increase the effective path length for diffusion and consequently limit the absorption of the solvent by occupation free volumes in the material. According to physico chemical properties of the two used solvents, it is found that the diffusion is more important for the toluene molecules solvent due to their low values of the molecular weight and volume molar compared to those for the xylene. Differential Scanning Calorimetry (DSC) and X-ray photo electron (XPS) were also used to probe the eventual change in the chemical composition for the swollen samples. Mechanically speaking, the stress-strain curves of uniaxial tensile tests pre- and post- swelling highlight a remarkably decrease of the strength and elongation at break of the swollen samples. This behavior can be attributed to the decrease of the load transfer density between the matrix and the CB in the presence of the solvent. We believe that the results reported in this experimental investigation can be useful for some demanding applications e.g. tires, sealing rubber.

Keywords: nanocomposite, absorption kinetics, mechanical behavior, diffusion, modelling, XPS, DSC

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1626 English Language Proficiency and Use as Determinants of Transactional Success in Gbagi Market, Ibadan, Nigeria

Authors: A. Robbin

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Language selection can be an efficient negotiation strategy employed by both service or product providers and their customers to achieve transactional success. The transactional scenario in Gbagi Market, Ibadan, Nigeria provides an appropriate setting for the exploration of the Nigerian multilingual situation with its own interesting linguistic peculiarities which questions the functionality of the ‘Lingua Franca’ in trade situations. This study examined English Language proficiency among Yoruba Traders in Gbagi Market, Ibadan and its use as determinants of transactional success during service encounters. Randomly selected Yoruba-English bilingual traders and customers were administered questionnaires and the data subjected to statistical and descriptive analysis using Giles Communication Accommodation Theory. Findings reveal that only fifty percent of the traders used for the study were proficient in speaking English language. Traders with minimal proficiency in Standard English, however, resulted in the use of the Nigerian Pidgin English. Both traders and customers select the Mother Tongue, which is the Yoruba Language during service encounters but are quick to converge to the other’s preferred language as the transactional exchange demands. The English language selection is not so much for the prestige or lingua franca status of the language as it is for its functions, which include ease of communication, negotiation, and increased sales. The use of English during service encounters is mostly determined by customer’s linguistic preference which the trader accommodates to for better negotiation and never as a first choice. This convergence is found to be beneficial as it ensures sales and return patronage. Although the English language is not a preferred code choice in Gbagi Market, it serves a functional trade strategy for transactional success during service encounters in the market.

Keywords: communication accommodation theory, language selection, proficiency, service encounter, transaction

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1625 Communicating Meaning through Translanguaging: The Case of Multilingual Interactions of Algerians on Facebook

Authors: F. Abdelhamid

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Algeria is a multilingual speech community where individuals constantly mix between codes in spoken discourse. Code is used as a cover term to refer to the existing languages and language varieties which include, among others, the mother tongue of the majority Algerian Arabic, the official language Modern Standard Arabic and the foreign languages French and English. The present study explores whether Algerians mix between these codes in online communication as well. Facebook is the selected platform from which data is collected because it is the preferred social media site for most Algerians and it is the most used one. Adopting the notion of translanguaging, this study attempts explaining how users of Facebook use multilingual messages to communicate meaning. Accordingly, multilingual interactions are not approached from a pejorative perspective but rather as a creative linguistic behavior that multilingual utilize to achieve intended meanings. The study is intended as a contribution to the research on multilingualism online because although an extensive literature has investigated multilingualism in spoken discourse, limited research investigated it in the online one. Its aim is two-fold. First, it aims at ensuring that the selected platform for analysis, namely Facebook, could be a source for multilingual data to enable the qualitative analysis. This is done by measuring frequency rates of multilingual instances. Second, when enough multilingual instances are encountered, it aims at describing and interpreting some selected ones. 120 posts and 16335 comments were collected from two Facebook pages. Analysis revealed that third of the collected data are multilingual messages. Users of Facebook mixed between the four mentioned codes in writing their messages. The most frequent cases are mixing between Algerian Arabic and French and between Algerian Arabic and Modern Standard Arabic. A focused qualitative analysis followed where some examples are interpreted and explained. It seems that Algerians mix between codes when communicating online despite the fact that it is a conscious type of communication. This suggests that such behavior is not a random and corrupted way of communicating but rather an intentional and natural one.

Keywords: Algerian speech community, computer mediated communication, languages in contact, multilingualism, translanguaging

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1624 The Development, Validation, and Evaluation of the Code Blue Simulation Module in Improving the Code Blue Response Time among Nurses

Authors: Siti Rajaah Binti Sayed Sultan

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Managing the code blue event is stressful for nurses, the patient, and the patient's families. The rapid response from the first and second responders in the code blue event will improve patient outcomes and prevent tissue hypoxia that leads to brain injury and other organ failures. Providing 1 minute for the cardiac massage and 2 minutes for defibrillation will significantly improve patient outcomes. As we know, the American Heart Association came out with guidelines for managing cardiac arrest patients. The hospital must provide competent staff to manage this situation. It can be achieved when the staff is well equipped with the skill, attitude, and knowledge to manage this situation with well-planned strategies, i.e., clear guidelines for managing the code blue event, competent staff, and functional equipment. The code blue simulation (CBS) was chosen in the training program for code blue management because it can mimic real scenarios. Having the code blue simulation module will allow the staff to appreciate what they will face during the code blue event, especially since it rarely happens in that area. This CBS module training will help the staff familiarize themselves with the activities that happened during actual events and be able to operate the equipment accordingly. Being challenged and independent in managing the code blue in the early phase gives the patient a better outcome. The CBS module will help the assessor and the hospital management team with the proper tools and guidelines for managing the code blue drill accordingly. As we know, prompt action will benefit the patient and their family. It also indirectly increases the confidence and job satisfaction among the nurses, increasing the standard of care, reducing the complication and hospital burden, and enhancing cost-effective care.

Keywords: code blue simulation module, development of code blue simulation module, code blue response time, code blue drill, cardiorespiratory arrest, managing code blue

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1623 Rapid Proliferation of Tissue Culture Using of Olive (Olea Europea L.) cv.Zard

Authors: Majid Gharaipour Abbasabad

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This research is studying the effects that various densities of Zeatin, and BA hormones may have on the scale of transformation of plant nodes to new shoots, among seedlings produced by seed germination, and also surveys the amount of produced shoots and their lengths, inside the specific Olive seed lab medium (OM). It is also concerned with the effects that various densities of IBA hormone, and inoculating the shoots with Agrobacterium Rhizogenez A4 can have on shoots' root production. This is a totally random research, and each attendance group has had three occurrences, and ten samples per a hectare. The average amounts have been compared using Duncan's test method, which was done in 5% level. The results indicated that the highest rate of transformation of micro samples to shoots happened in the seed germination environments, containing Zetain with 5 mg, and also 15 mg per a liter densities. (respectively, 95% and 94%), while the highest rate of plants' stem production ,in micro samples, happened in the lab medium environments with 5mg per a liter Zetain density (4.5). In lab medium environments with 15 mg Zetain per liter, a decrease was observed in the number of produced stems (3.88). According to the produced stems' lenght, the longest stem length was observed in environments with 5 mg and also 15 mg per a liter Zetain, and 25 mg per a liter BA densities (respectively, 8.45 cm, 45.66 cm, 8.53 cm). Meanwhile, the lowest amount of transformation of micro samples to shoots, the lowest number of produced shoots, and the shortest shoots were observed in the environments without any hormones (respectively, 3.32 cm, 1.13, 19.66%). The results of root production in Olive indicated that attendance groups which were exposed to different hormones did not vary, and Agrobacterium Rhizogenez A4 had no effect on them, as well. The lowest root's growth rate (22%) happened in environments without any hormones and also, in environment with Agrobacterium Rhizogenez A4 (19.66%). The largest number of roots was observed in the environments, containing Agrobacterium Rhizogenez A4 plus IBA (10 mg/l) and Agrobacterium Rhizogenez A4 plus IBA (10 mg/l), (respectively, 8.46 and 8.70), which had a significant difference with environments merely containing 10 mg and 20 mg of IBA per a litre (respectively, 3.06 and 3.2). So it can be concluded that even though Agrobacterium Rhizogenez A4 had no impact on root's growth among shoots, it had an impact on the number of produced roots. It should be noted that even when the environment contained merely Agrobacterium Rhizogenez A4 without any hormones, only (1.16) roots were produced, which is significantly different from the attendance group with hormones (1.06).

Keywords: olive-effect of hormones-germination of seed, densities of zeatin, BA hormones, agriculture

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1622 Prebiotics and Essential Oils-Enriched Diet Can Increase the Efficiency of Vaccine against Furunculosis in Rainbow Trout (Oncorhynchus Mykiss)

Authors: Niki Hayatgheib, SéGolèNe Calvez, Catherine Fournel, Lionel Pineau, Herve Pouliquen, Emmanuelle Moreau

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Furunculosis caused by infection with Aeromonas salmonicida subsp. salmonicida has been a known disease found principally in salmonid aquaculture. Vaccination has been partly successful in preventing this disease, but outbreaks still occur. The application of functional feed additive found to be a promising yield to improve fish health against diseases. In this study, we tested the efficacy of prebiotics and plant essential oils-enriched diet on immune response and disease resistance in vaccinated and non-vaccinated rainbow trout (Oncorhynchus mykiss) against furunculosis. A total of 600 fish were fed with the basal diet or supplement. On 4th week of feeding, fish were vaccinated with an autovaccine. Following 8 weeks, fish were challenged with Aeromonas salmonicida subsp. salmonicida and mortalities were recorded for 3 weeks. Lysozyme activity and antibody titer in serum were measured in different groups. The results of this study showed that lysozyme and circulatory antibody titer in plasma elevated significantly in vaccinated fish fed with additive. The best growth rate and relative percentage survival (62%) were in fish fed with a supplement, while 15% in control fish. Overall, prebiotics and essential oils association can be considered as a potential component for enhancing vaccine efficacy against furunculosis by increasing the growth performance, immune responses and disease resistance in rainbow trout.

Keywords: aeromonas salmonicida subsp. salmonicida, aquaculture, disease resistance, fish, immune response, prebiotics-essential oils feed additive, rainbow trout, vaccination

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1621 Preparation of Chemically Activated Carbon from Waste Tire Char for Lead Ions Adsorption and Optimization Using Response Surface Methodology

Authors: Lucky Malise, Hilary Rutto, Tumisang Seodigeng

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The use of tires in automobiles is very important in the automobile industry. However, there is a serious environmental problem concerning the disposal of these rubber tires once they become worn out. The main aim of this study was to prepare activated carbon from waste tire pyrolysis char by impregnating KOH on pyrolytic char. Adsorption studies on lead onto chemically activated carbon was carried out using response surface methodology. The effect of process parameters such as temperature (°C), adsorbent dosage (g/1000ml), pH, contact time (minutes) and initial lead concentration (mg/l) on the adsorption capacity were investigated. It was found that the adsorption capacity increases with an increase in contact time, pH, temperature and decreases with an increase in lead concentration. Optimization of the process variables was done using a numerical optimization method. Fourier Transform Infrared Spectra (FTIR) analysis, XRay diffraction (XRD), Thermogravimetric analysis (TGA) and scanning electron microscope was used to characterize the pyrolytic carbon char before and after activation. The optimum points 1g/ 100 ml for adsorbent dosage, 7 for pH value of the solution, 115.2 min for contact time, 100 mg/l for initial metal concentration, and 25°C for temperature were obtained to achieve the highest adsorption capacity of 93.176 mg/g with a desirability of 0.994. Fourier Transform Infrared Spectra (FTIR) analysis and Thermogravimetric analysis (TGA) show the presence of oxygen-containing functional groups on the surface of the activated carbon produced and that the weight loss taking place during the activation step is small.

Keywords: waste tire pyrolysis char, chemical activation, central composite design (CCD), adsorption capacity, numerical optimization

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1620 The Effects of a Nursing Dignity Care Program on Patients’ Dignity in Care

Authors: Yea-Pyng Lin

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Dignity is a core element of nursing care. Maintaining the dignity of patients is an important issue because the health and recovery of patients can be adversely affected by a lack of dignity in their care. The aim of this study was to explore the effects of a nursing dignity care program upon patients’ dignity in care. A quasi-experimental research design was implemented. Nurses were recruited by purposive sampling, and their patients were recruited by simple random sampling. Nurses in the experimental group received the nursing educational program on dignity care, while nurses in the control group received in-service education as usual. Data were collected via two instruments: the dignity in care scale for nurses and the dignity in care scale to patients, both of which were developed by the researcher. Both questionnaires consisted of three domains: agreement, importance, and frequencies of providing dignity care. A total of 178 nurses in the experimental group and 193 nurses in the control group completed the pretest and the follow-up evaluations at the first month, the third month, and the sixth month. The number of patients who were cared for by the nurses in the experimental group was 94 in the pretest. The number of patients in the post-test at the first, third, and sixth months were 91, 85, and 77, respectively. In the control group, 88 patients completed the II pretest, and 80 filled out the post-test at the first month, 77 at the third, and 74 at the sixth month. The major findings revealed the scores of agreement domain among nurses in the experimental group were found significantly different from those who in the control group at each point of time. The scores of importance domain between these two groups also displayed significant differences at pretest and the first month of post-test. Moreover, the frequencies of proving dignity care to patients were significant at pretest, the third month and sixth month of post-test. However, the experimental group had only significantly different from those who in the control group on the frequencies of receiving dignity care especially in the items of ‘privacy care,’ ‘communication care,’ and ‘emotional care’ for the patients. The results show that the nursing program on dignity care could increase nurses’ dignity care for patients in three domains of agreement, importance, and frequencies of providing dignity care. For patients, only the frequencies of receiving dignity care were significantly increased. Therefore, the nursing program on dignity care could be applicable for nurses’ in-service education and practice to enhance the ability of nurses to care for patient’s dignity.

Keywords: nurses, patients, dignity care, quasi-experimental, nursing education

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1619 Knowledge of Risk Factors and Health Implications of Fast Food Consumption among Undergraduate in Nigerian Polytechnic

Authors: Adebusoye Michael, Anthony Gloria, Fasan Temitope, Jacob Anayo

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Background: The culture of fast food consumption has gradually become a common lifestyle in Nigeria especially among young people in urban areas, in spite of the associated adverse health consequences. The adolescent pattern of fast foods consumption and their perception of this practice, as a risk factor for Non-Communicable Diseases (NCDs), have not been fully explored. This study was designed to assess fast food consumption pattern and the perception of it as a risk factor for NCDs among undergraduates of Federal Polytechnic, Bauchi. Methodology: The study was descriptive cross-sectional in design. One hundred and eighty-five students were recruited using systematic random sampling method from the two halls of residence. A structured questionnaire was used to assess the consumption pattern of fast foods. Data collected from the questionnaires were analysed using statistical package for the social sciences (SPSS) version 16. Simple descriptive statistics, such as frequency counts and percentages were used to interpret the data. Results: The age range of respondents was 18-34 years, 58.4% were males, 93.5% singles and 51.4% of their parents were employed. The majority (100%) were aware of fast foods and (75%) agreed to its implications as NCD. Fast foods consumption distribution included meat pie (4.9%), beef roll/ sausage (2.7%), egg roll (13.5%), doughnut (16.2%), noodles(18%) and carbonated drinks (3.8%). 30.3% consumed thrice in a week and 71% attached workload to high consumption of fast food. Conclusion: It was revealed that a higher social pressure from peers, time constraints, class pressure and school programme had the strong influence on high percentages of higher institutions’ students consume fast foods and therefore nutrition educational campaigns for campus food outlets or vendors and behavioural change communication on healthy nutrition and lifestyles among young people are hereby advocated.

Keywords: fast food consumption, Nigerian polytechnic, risk factors, undergraduate

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1618 An Investigation into the Crystallization Tendency/Kinetics of Amorphous Active Pharmaceutical Ingredients: A Case Study with Dipyridamole and Cinnarizine

Authors: Shrawan Baghel, Helen Cathcart, Biall J. O'Reilly

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Amorphous drug formulations have great potential to enhance solubility and thus bioavailability of BCS class II drugs. However, the higher free energy and molecular mobility of the amorphous form lowers the activation energy barrier for crystallization and thermodynamically drives it towards the crystalline state which makes them unstable. Accurate determination of the crystallization tendency/kinetics is the key to the successful design and development of such systems. In this study, dipyridamole (DPM) and cinnarizine (CNZ) has been selected as model compounds. Thermodynamic fragility (m_T) is measured from the heat capacity change at the glass transition temperature (Tg) whereas dynamic fragility (m_D) is evaluated using methods based on extrapolation of configurational entropy to zero 〖(m〗_(D_CE )), and heating rate dependence of Tg 〖(m〗_(D_Tg)). The mean relaxation time of amorphous drugs was calculated from Vogel-Tammann-Fulcher (VTF) equation. Furthermore, the correlation between fragility and glass forming ability (GFA) of model drugs has been established and the relevance of these parameters to crystallization of amorphous drugs is also assessed. Moreover, the crystallization kinetics of model drugs under isothermal conditions has been studied using Johnson-Mehl-Avrami (JMA) approach to determine the Avrami constant ‘n’ which provides an insight into the mechanism of crystallization. To further probe into the crystallization mechanism, the non-isothermal crystallization kinetics of model systems was also analysed by statistically fitting the crystallization data to 15 different kinetic models and the relevance of model-free kinetic approach has been established. In addition, the crystallization mechanism for DPM and CNZ at each extent of transformation has been predicted. The calculated fragility, glass forming ability (GFA) and crystallization kinetics is found to be in good correlation with the stability prediction of amorphous solid dispersions. Thus, this research work involves a multidisciplinary approach to establish fragility, GFA and crystallization kinetics as stability predictors for amorphous drug formulations.

Keywords: amorphous, fragility, glass forming ability, molecular mobility, mean relaxation time, crystallization kinetics, stability

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1617 An Exploration of Renewal Utilization of Under-bridge Space Based on Spatial Potential Evaluation - Taking Chongqing Municipality as an Example

Authors: Xuelian Qin

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Urban "organic renewal" based on the development of existing resources in high-density urban areas has become the mainstream of urban development in the new era. As an important stock resource of public space in high-density urban areas, promoting its value remodeling is an effective way to alleviate the shortage of public space resources. However, due to the lack of evaluation links in the process of underpass space renewal, a large number of underpass space resources have been left idle, facing the problems of low space conversion efficiency, lack of accuracy in development decision-making, and low adaptability of functional positioning to citizens' needs. Therefore, it is of great practical significance to construct the evaluation system of under-bridge space renewal potential and explore the renewal mode. In this paper, some of the under-bridge spaces in the main urban area of Chongqing are selected as the research object. Through the questionnaire interviews with the users of the built excellent space under the bridge, three types of six levels and twenty-two potential evaluation indexes of "objective demand factor, construction feasibility factor and construction suitability factor" are selected, including six levels of land resources, infrastructure, accessibility, safety, space quality and ecological environment. The analytical hierarchy process and expert scoring method are used to determine the index weight, construct the potential evaluation system of the space under the bridge in high-density urban areas of Chongqing, and explore the direction of renewal and utilization of its suitability. To provide feasible theoretical basis and scientific decision support for the use of under bridge space in the future.

Keywords: high density urban area, potential evaluation, space under bridge, updated using

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1616 Multifunctional β-Cyclodextrin-EDTA-Chitosan Polymer Adsorbent Synthesis for Simultaneous Removal of Heavy Metals and Organic Dyes from Wastewater

Authors: Monu Verma, Hyunook Kim

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Heavy metals and organic dyes are the major sources of water pollution. Herein, a trifunctional β−cyclodextrin−ethylenediaminetetraacetic acid−chitosan (β−CD−EDTA−CS) polymer was synthesized using an easy and simple chemical route by the reaction of activated β−CD with CS through EDTA as a cross-linker (amidation reaction) for the removal of inorganic and organic pollutants from aqueous solution under different parameters such as pH, time effect, initial concentration, reusability, etc. The synthesized adsorbent was characterized using powder X-ray diffraction, Fourier transform infrared spectroscopy, field scanning electron microscopy, energy dispersive spectroscopy, Brunauer-Emmett-Teller (BET), thermogravimetric analyzer techniques to investigate their structural, functional, morphological, elemental compositions, surface area, and thermal properties, respectively. Two types of heavy metals, i.e., mercury (Hg²⁺) and cadmium (Cd²⁺), and three organic dyes, i.e., methylene blue (MB), crystal violet (CV), and safranin O (SO), were chosen as inorganic and organic pollutants, respectively, to study the adsorption capacity of β-CD-EDTA-CS in aqueous solution. The β-CD-EDTA-CS shows a monolayer adsorption capacity of 346.30 ± 14.0 and 202.90 ± 13.90 mg g−¹ for Hg²⁺ and Cd²⁺, respectively, and a heterogeneous adsorption capacity of 107.20 ± 5.70, 77.40 ± 5.30 and 55.30 ± 3.60 mg g−¹ for MB, CV and SO, respectively. Kinetics results followed pseudo-second order (PSO) kinetics behavior for both metal ions and dyes, and higher rate constants values (0.00161–0.00368 g mg−¹ min−¹) for dyes confirmed the cavitation of organic dyes (physisorption). In addition, we have also demonstrated the performance of β-CD-EDTA-CS for the four heavy metals, Hg²⁺, Cd²⁺, Ni²⁺, and Cu²⁺, and three dyes MB, CV, and SO in secondary treated wastewater. The findings of this study indicate that β-CD-EDTA-CS is simple and easy to synthesize and can be used in wastewater treatment.

Keywords: adsorption isotherms, adsorption mechanism, amino-β-cyclodextrin, heavy metal ions, organic dyes

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1615 Distributive School Leadership in Croatian Primary Schools

Authors: Iva Buchberger, Vesna Kovač

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Global education policy trends and recommendations underline the importance of (distributive) school leadership as a school effectiveness key factor. In this context, the broader aim of this research (supported by the Croatian Science Foundation) is to identify school leadership characteristics in Croatian schools and to examine the correlation between school leadership and school effectiveness. The aim of the proposed conference paper is to focus on the school leadership characteristics which are additionally explained with school leadership facilitators that contribute to (distributive) school leadership development. The aforementioned school leadership characteristics include the following dimensions: (a) participation in the process of making different types of decisions, (b) influence in the decision making process, (c) social interactions between different stakeholders in the decision making process in schools. Further, the school leadership facilitators are categorized as follows: (a) principal’s activities (such as providing support to different stakeholders and developing mutual trust among them), (b) stakeholders’ characteristics (such as developed stakeholders’ interest and competence to participate in decision-making process), (c) organizational and material resources (such as school material conditions, the necessary information and time as resources for making decisions). The data were collected by a constructed and validated questionnaire for examining the school leadership characteristics and facilitators from teachers’ perspective. The main population in this study consists of all primary schools in Croatia while the sample is comprised of 100 primary schools, selected by random sampling. Furthermore, the sample of teachers was selected by an additional procedure taking into consideration the independent variables of sex, work experience, etc. Data processing was performed by standard statistical methods of descriptive and inferential statistics. Statistical program IBM SPSS 20.0 was used for data processing. The results of this study show that there is a (positive) correlation between school leadership characteristics and school leadership facilitators. Specifically, it is noteworthy to mention that all the dimensions of school leadership characteristics are in positive correlation with the categories of school leadership facilitators. These results are indicative for the education policy creators who should ensure positive and supportive environment for the school leadership development including the development of school leadership characteristics and school leadership facilitators.

Keywords: distributive school leadership, school effectiveness , school leadership characteristics, school leadership facilitators

Procedia PDF Downloads 233