Search results for: curing agent
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1843

Search results for: curing agent

883 The Influence of Mineraliser Granulometry on Dense Silica Brick Microstructure

Authors: L. Nevrivova, K. Lang, M. Kotoucek, D. Vsiansky

Abstract:

This entry concerned with dense silica microstructure was produced as a part of a project within the Technology Agency of the Czech Republic which is being implemented in cooperation of the biggest producer of refractories the P-D Refractories CZ company with the research organisation Brno University of Technology. The paper is focused on the influence of mixture homogenisation and the influence of grain size of the mineraliser on the resulting utility properties of the material as well as its microstructure. It has a decisive influence on the durability of the material in a building structure. This paper is a continuation of a previously published study dealing with the suitability of various types of mineralising agents in terms of density, strength and mineral composition of silica. The entry describes the influence of the method of mixture homogenisation and the influence of granulometry of the applied Fe-mineralising agent on the resulting silica microstructure. Porosity, density, phase composition and microstructure of the experimentally prepared silica samples were examined and the results were discussed in context with the technology of homogenisation and firing temperature used. The properties of silica brick samples were compared to the sample without any Fe-mineraliser.

Keywords: silica bricks, Fe-mineraliser, mineralogical composition, new developed silica material

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882 Innovative Grafting of Polyvinylpyrrolidone onto Polybenzimidazole Proton Exchange Membranes for Enhanced High-Temperature Fuel Cell Performance

Authors: Zeyu Zhou, Ziyu Zhao, Xiaochen Yang, Ling AI, Heng Zhai, Stuart Holmes

Abstract:

As a promising sustainable alternative to traditional fossil fuels, fuel cell technology is highly favoured due to its enhanced working efficiency and reduced emissions. In the context of high-temperature fuel cells (operating above 100 °C), the most commonly used proton exchange membrane (PEM) is the Polybenzimidazole (PBI) doped phosphoric acid (PA) membrane. Grafting is a promising strategy to advance PA-doped PBI PEM technology. The existing grafting modification on PBI PEMs mainly focuses on grafting phosphate-containing or alkaline groups onto the PBI molecular chains. However, quaternary ammonium-based grafting approaches face a common challenge. To initiate the N-alkylation reaction, deacidifying agents such as NaH, NaOH, KOH, K2CO3, etc., can lead to ionic crosslinking between the quaternary ammonium group and PBI. Polyvinylpyrrolidone (PVP) is another widely used polymer, the N-heterocycle groups within PVP endow it with a significant ability to absorb PA. Recently, PVP has attracted substantial attention in the field of fuel cells due to its reduced environmental impact and impressive fuel cell performance. However, due to the the poor compatibility of PVP in PBI, few research apply PVP in PA-doped PBI PEMs. This work introduces an innovative strategy to graft PVP onto PBI to form a network-like polymer. Due to the absence of quaternary ammonium groups, PVP does not pose issues related to crosslinking with PBI. Moreover, the nitrogen-containing functional groups on PVP provide PBI with a robust phosphoric acid retention ability. The nuclear magnetic resonance (NMR) hydrogen spectrum analysis results indicate the successful completion of the grafting reaction where N-alkylation reactions happen on both sides of the grafting agent 1,4-bis(chloromethyl)benzene. On one side, the reaction takes place with the hydrogen atoms on the imidazole groups of PBI, while on the other side, it reacts with the terminal amino group of PVP. The XPS results provide additional evidence from the perspective of the element. On synthesized PBI-g-PVP surfaces, there is an absence of chlorine (chlorine in grafting agent 1,4-bis(chloromethyl)benzene is substituted) element but a presence of sulfur element (sulfur element in terminal amino PVP appears in PBI), which demonstrates the occurrence of the grafting reaction and PVP is successfully grafted onto PBI. Prepare these modified membranes into MEA. It was found that during the fuel cell operation, all the grafted membranes showed substantial improvement in maximum current density and peak power density compared to unmodified one. For PBI-g-PVP 30, with a grafting degree of 22.4%, the peak power density reaches 1312 mW cm⁻², marking a 59.6% enhancement compared to the pristine PBI membrane. The improvement is caused by the improved PA binding ability of the membrane after grafting. The AST test result shows that the grafting membranes have better long-term durability and performance than unmodified membranes attributed to the presence of added PA binding sites, which can effectively prevent the PA leaching caused by proton migration. In conclusion, the test results indicate that grafting PVP onto PBI is a promising strategy which can effectively improve the fuel cell performance.

Keywords: fuel cell, grafting modification, PA doping ability, PVP

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881 Preparation of Novel Antimicrobial Meat Packaging Using Chitosan-Arginine

Authors: R. A. Lahmer, A. P. Williams, S. Townsend, S. Baker, D. L. Jones

Abstract:

Chitosan-arginine (Ch-arg) has been proposed as an anti-microbial agent to reduce the proliferation of spoilage and pathogenic bacteria within meat products destined for human consumption. In the current experiment its use as an antimicrobial packaging material was examined. Two different concentrations of chitosan-arginine (0.05 and 0.15 % w/w) were blended into a cellulose film (Ch-arg film). When placed in contact with chicken and beef juice inoculated with a lux-marked strain of E. coli O157, the film incorporating the highest Ch-arg concentration resulted in a small reduction of E. coli O157 in chicken juice; however, there was no effect of the Ch-arg film on E. coli O157 in beef juice. The lack of observed effect in the beef juice experiment we ascribe to insufficient surface-to-surface contact between the film and the bacteria in the beef juice and the greater presence of other Ch-arg reactive components in the juice (e.g. fats, blood cells). Results suggest that, in combination with other anti microbials, Ch-arg packaging may offers some potential for limiting the growth of pathogenic bacteria in foodstuffs; however, further research is needed to enhance their anti-microbial performance.

Keywords: cross-contamination, foodborne pathogen, polymer film, shelf life

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880 Dynamic Effects of Charitable Giving in a Ramsey Model

Authors: Riham Barbar

Abstract:

This paper studies the dynamic effects of charitable giving in a Ramsey model à la Becker and Foias (1994), such that heterogeneity is reduced to two types of agents: rich and poor. It is assumed that rich show a great concern for poor and enjoy giving. The introduction of charitable giving in this paper is inspired from the notion of Zakat (borrowed from the Islamic Economics) and is defined according to the warm-glow of Andreoni (1990). In this framework, we prove the existence of a steady state where only the patient agent holds capital. Furthermore, we show that local indetermincay appears. While moderate values of charitable-giving elasticity makes the appearance of endogenous fluctuations due to self-fulfilling expectations more likely, high values of this elasticity stabilizes endogenous fluctuations, by narrowing down the range of parameter values compatible with local indeterminacy and may rule out expectations-driven fluctuations if it exceeds certain threshold. Finally, cycles of period two emerge. However, charitable-giving makes it less likely for these cycles to emerge.

Keywords: charitable giving, warm-glow, bifurcations, heterogeneous agents, indeterminacy, self-fulfilling expectations, endogenous fluctuations

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879 Experimental Investigation on the Effects of Electroless Nickel Phosphorus Deposition, pH and Temperature with the Varying Coating Bath Parameters on Impact Energy by Taguchi Method

Authors: D. Kari Basavaraja, M. G. Skanda, C. Soumya, V. Ramesh

Abstract:

This paper discusses the effects of sodium hypophosphite concentration, pH, and temperature on deposition rate. This paper also discusses the evaluation of coating strength, surface, and subsurface by varying the bath parameters, percentage of phosphate, plating temperature, and pH of the plating solution. Taguchi technique has been used for the analysis. In the experiment, nickel chloride which is a source of nickel when mixed with sodium hypophosphite has been used as the reducing agent and the source of phosphate and sodium hydroxide has been used to vary the pH of the coating bath. The coated samples are tested for impact energy by conducting impact test. Finally, the effects of coating bath parameters on the impact energy absorbed have been plotted, and analysis has been carried out. Further, percentage contribution of coating bath parameters using Design of Experiments approach (DOE) has been analysed. Finally, it can be concluded that the bath parameters of the Ni-P coating will certainly influence on the strength of the specimen.

Keywords: bath parameters, coatings, design of experiment, fracture toughness, impact strength

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878 Synthesis, Biological Evaluation and Molecular Modeling Studies on Chiral Chloroquine Analogues as Antimalarial Agents

Authors: Srinivasarao Kondaparla, Utsab Debnath, Awakash Soni, Vasantha Rao Dola, Manish Sinha, Kumkum Kumkum Srivastava, Sunil K. Puri, Seturam B. Katti

Abstract:

In a focused exploration, we have designed synthesized and biologically evaluated chiral conjugated new chloroquine (CQ) analogs with substituted piperazines as antimalarial agents. In vitro as well as in vivo studies revealed that compound 7c showed potent activity [for in vitro IC₅₀= 56.98nM (3D7), 97.76nM (K1); for in vivo (up to at the dose of 12.5 mg/kg); SI = 3510] as a new lead of antimalarial agent. Other compounds 6b, 6d, 7d, 7h, 8c, 8d, 9a, and 9c are also showing moderate activity against CQ-sensitive (3D7) strain and superior activity against resistant (K1) strain of P. falciparum. Furthermore, we have carried out docking and 3D-QSAR studies of all in-house data sets (168 molecules) of chiral CQ analogs to explain the structure activity relationships (SAR). Our new findings specified the significance of H-bond interaction with the side chain of heme for biological activity. In addition, the 3D-QSAR study against 3D7 strain indicated the favorable and unfavorable sites of CQ analogs for incorporating steric, hydrophobic and electropositive groups to improve the antimalarial activity.

Keywords: piperazines, CQ-sensitive strain-3D7, in-vitro and in-vivo assay, docking, 3D-QSAR

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877 GSM Based Smart Patient Monitoring System

Authors: Ayman M. Mansour

Abstract:

In this paper, we propose an intelligent system that is used for monitoring the health conditions of Patients. Monitoring the health condition of Patients is a complex problem that involves different medical units and requires continuous monitoring especially in rural areas because of inadequate number of available specialized physicians. The proposed system will Improve patient care and drive costs down comparing to the existing system in Jordan. The proposed system will be the start point to Faster and improve the communication between different units in the health system in Jordan. Connecting patients and their physicians beyond hospital doors regarding their geographical area is an important issue in developing the health system in Jordan. The propose system will provide an intelligent system that will generate initial diagnosing to the patient case. This will assist and advice clinicians at the point of care. The decision is based on demographic data and laboratory test results of patient data. Using such system with the ability of making medical decisions, the quality of medical care in Jordan and specifically in Tafial is expected to be improved. This will provide more accurate, effective, and reliable diagnoses and treatments especially if the physicians have insufficient knowledge.

Keywords: GSM, SMS, patient, monitoring system, fuzzy logic, multi-agent system

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876 Mapping the Relationship between Elements of Urban Morphology Density of Crime

Authors: Fabio Salvador Aparecido Santos, Spencer Chainey, Richard Wortley

Abstract:

Urban morphology can be understood as the study of the physical form of cities through its elements. Crime, at this turn, can be oversimplified as an action that breaks the rules established in a certain society. This study involves these two subjects through the relationship between elements of urban morphology and density of crime occurrences. We consider that there is a research gap about the influence of urban features on crime occurrences using statistic methods and mapping techniques on Geographic Information Systems. The investigation will comprehend three main phases. The first phase involves examining how theoretical principles associated with urban morphology can be viewed in terms of their influence on crime patterns. The second phase involves the development of tools to be used to model elements of urban morphology, and measure the relationship between these urban morphological elements and patterns of crime. The third phase involves determining the extent to which elements of the urban environment can contribute to crime reduction. Understanding the relationship between urban morphology and crime patterns in a Latin American context will help highlight the influence urban planning has on the crime problems that emerge in these settings, and how effectively urban planning can contribute to reducing crime.

Keywords: Agent-based Modelling, Environmental Criminology, Geographic Information System, Urban Morphology

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875 Interaction of Steinernema Glaseri, an Entomopathogenic Nematode with a Predatory Fungus Arthrobotrys Superba on Different Nutrient Media

Authors: Varsha Baweja

Abstract:

Steinernema glaseri is known to be the most potent biocontrol agent against a number of insect pests of various orders and of diverse habitats under laboratory conditions. But in nature many micro pathogens may affect the efficacy of such entomopathogenic nematodes. Keeping this in view, the interaction of Steinernema glaseri with a predatory fungus Arthrobotrys superba was assessed on eight different nutrient media. The activity of A.superba was evaluated in terms of trap formation, conidiophore formation, and number of adhesive cells formed in the presence and absence of nematodes. The fungus failed to form any trap on any of the culture media in the absence of nematodes. However, in the presence of nematodes, the trap formation by the test fungus was increased but the number of conidiophores decreased with increase in dilution of Corn Meal Agar from 5% to 2%. Higher number of chlamydospores were observed in phenylalanine treated medium which indicates the inhibiting effect of phenylalanine on the growth of A. superba. Our results suggest that care should be taken during release of entomopathogenic nematodes in an agroecosystem for managing various insect pests in a more efficient manner.

Keywords: Entomopathogenic Nematode , Steinernema Glaseri, Predatory Fungus, Arthrobotrys Superba

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874 Kinetic and Thermodynamic Modified Pectin with Chitosan by Forming Polyelectrolyte Complex Adsorbent to Remediate of Pb(II)

Authors: Budi Hastuti, Mudasir, Dwi Siswanta, Triyono

Abstract:

Biosorbent, such as pectin and chitosan, are usually produced with low physical stability, thus the materials need to be modified. In this research, the physical characteristic of adsorbent was increased by grafting chitosan using acetate carboxymetyl chitosan (CC). Further, CC and Pectin (Pec) were crosslinked using cross-linking agent BADGE (bis phenol A diglycidyl ether) to get CC-Pec-BADGE (CPB) adsorbent. The cross-linking processes aim to form stable structure and resistance on acidic media. Furthermore, in order to increase the adsorption capacity in removing Pb(II), the adsorbent was added with NaCl to form macroporous adsorbent named CCPec-BADGE-Na (CPB-Na). The physical and chemical characteristics of the porogenic adsorbent structure were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). The adsorption parameter of CPB-Na to adsorb Pb(II) ion was determined. The kinetics and thermodynamics of the bath sorption of Pb(II) on CPB-Na adsorbent and using chitosan and pectin as a comparison were also studied. The results showed that the CPB-Na biosorbent was stable on acidic media. It had a rough and porous surface area, increased and gave higher sorption capacity for removal of Pb(II) ion. The CPB-Na 1/1 and 1/3 adsorbent adsorbed Pb(II) with adsorption capacity of 45.48 mg/g and 45.97 mg/g respectively, whereas pectin and chitosan were of 39.20 mg /g and 24.67 mg /g respectively.

Keywords: porogen, Pectin, Carboxymethyl Chitosan (CC), CC- Pec-BADGE-Na

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873 Influence of Deficient Materials on the Reliability of Reinforced Concrete Members

Authors: Sami W. Tabsh

Abstract:

The strength of reinforced concrete depends on the member dimensions and material properties. The properties of concrete and steel materials are not constant but random variables. The variability of concrete strength is due to batching errors, variations in mixing, cement quality uncertainties, differences in the degree of compaction and disparity in curing. Similarly, the variability of steel strength is attributed to the manufacturing process, rolling conditions, characteristics of base material, uncertainties in chemical composition, and the microstructure-property relationships. To account for such uncertainties, codes of practice for reinforced concrete design impose resistance factors to ensure structural reliability over the useful life of the structure. In this investigation, the effects of reductions in concrete and reinforcing steel strengths from the nominal values, beyond those accounted for in the structural design codes, on the structural reliability are assessed. The considered limit states are flexure, shear and axial compression based on the ACI 318-11 structural concrete building code. Structural safety is measured in terms of a reliability index. Probabilistic resistance and load models are compiled from the available literature. The study showed that there is a wide variation in the reliability index for reinforced concrete members designed for flexure, shear or axial compression, especially when the live-to-dead load ratio is low. Furthermore, variations in concrete strength have minor effect on the reliability of beams in flexure, moderate effect on the reliability of beams in shear, and sever effect on the reliability of columns in axial compression. On the other hand, changes in steel yield strength have great effect on the reliability of beams in flexure, moderate effect on the reliability of beams in shear, and mild effect on the reliability of columns in axial compression. Based on the outcome, it can be concluded that the reliability of beams is sensitive to changes in the yield strength of the steel reinforcement, whereas the reliability of columns is sensitive to variations in the concrete strength. Since the embedded target reliability in structural design codes results in lower structural safety in beams than in columns, large reductions in material strengths compromise the structural safety of beams much more than they affect columns.

Keywords: code, flexure, limit states, random variables, reinforced concrete, reliability, reliability index, shear, structural safety

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872 Mediation Models in Triadic Relationships: Illness Narratives and Medical Education

Authors: Yoko Yamada, Chizumi Yamada

Abstract:

Narrative psychology is based on the dialogical relationship between self and other. The dialogue can consist of divided, competitive, or opposite communication between self and other. We constructed models of coexistent dialogue in which self and other were positioned side by side and communicated sympathetically. We propose new mediation models for narrative relationships. The mediation models are based on triadic relationships that incorporate a medium or a mediator along with self and other. We constructed three types of mediation model. In the first type, called the “Joint Attention Model”, self and other are positioned side by side and share attention with the medium. In the second type, the “Triangle Model”, an agent mediates between self and other. In the third type, the “Caring Model”, a caregiver stands beside the communication between self and other. We apply the three models to the illness narratives of medical professionals and patients. As these groups have different views and experiences of disease or illness, triadic mediation facilitates the ability to see things from the other person’s perspective and to bridge differences in people’s experiences and feelings. These models would be useful for medical education in various situations, such as in considering the relationships between senior and junior doctors and between old and young patients.

Keywords: illness narrative, mediation, psychology, model, medical education

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871 A Particle Filter-Based Data Assimilation Method for Discrete Event Simulation

Authors: Zhi Zhu, Boquan Zhang, Tian Jing, Jingjing Li, Tao Wang

Abstract:

Data assimilation is a model and data hybrid-driven method that dynamically fuses new observation data with a numerical model to iteratively approach the real system state. It is widely used in state prediction and parameter inference of continuous systems. Because of the discrete event system’s non-linearity and non-Gaussianity, traditional Kalman Filter based on linear and Gaussian assumptions cannot perform data assimilation for such systems, so particle filter has gradually become a technical approach for discrete event simulation data assimilation. Hence, we proposed a particle filter-based discrete event simulation data assimilation method and took the unmanned aerial vehicle (UAV) maintenance service system as a proof of concept to conduct simulation experiments. The experimental results showed that the filtered state data is closer to the real state of the system, which verifies the effectiveness of the proposed method. This research can provide a reference framework for the data assimilation process of other complex nonlinear systems, such as discrete-time and agent simulation.

Keywords: discrete event simulation, data assimilation, particle filter, model and data-driven

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870 Production of Antimicrobial Agents against Multidrug-Resistant Staphylococcus aureus through the Biocatalysis of Vegetable Oils

Authors: Hak-Ryul Kim, Hyung-Geun Lee, Qi Long, Ching Hou

Abstract:

Structural modification of natural lipids via chemical reaction or microbial bioconversion can change their properties or even create novel functionalities. Enzymatic oxidation of lipids leading to formation of oxylipin is one of those modifications. Hydroxy fatty acids, one of those oxylipins have gained important attentions because of their structural and functional properties compared with other non-hydroxy fatty acids. Recently 7,10-dihydroxy-8(E)-octadecenoic acid (DOD) was produced with high yield from lipid-containing oleic acid by microbial conversion, and the further study confirmed that DOD contained strong antimicrobial activities against a broad range of microorganisms. In this study, we tried to modify DOD molecules by the enzymatic or physical reaction to create new functionality or to enhance the antimicrobial activity of DOD. After modification of DOD molecules by different ways, we confirmed that the antimicrobial activity of DOD was highly enhanced and presented strong antimicrobial activities against multidrug-resistant Staphylococcus aureus, suggesting that DOD and its derivatives can be used as efficient antimicrobial agents for medical and industrial applications.

Keywords: biocatalysis, antimicrobial agent, multidrug-resistant bacteria, vegetable oil

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869 The Analysis of Application of Green Bonds in New Energy Vehicles in China: From Evolutionary Game Theory

Authors: Jing Zhang

Abstract:

Sustainable development in the new energy vehicles field is the requirement of the net zero aim. Green bonds are accepted as a practical financial tool to boost the transformation of relevant enterprises. The paper analyzes the interactions among governments, enterprises of new energy vehicles, and financial institutions by an evolutionary game theory model and offers advice to stakeholders in China. The decision-making subjects of green behavior are affected by experiences, interests, perception ability, and risk preference, so it is difficult for them to be completely rational. Based on the bounded rationality hypothesis, this paper applies prospect theory in the evolutionary game analysis framework and analyses the costs of government regulation of enterprises adopting green bonds. The influence of the perceived value of revenue prospect and the probability and risk transfer coefficient of the government's active regulation on the decision-making agent's strategy is verified by numerical simulation. Finally, according to the research conclusions, policy suggestions are given to promote green bonds.

Keywords: green bonds, new energy vehicles, sustainable development, evolutionary Game Theory model

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868 Dye Retention by a Photochemicaly Crosslinked Poly(2-Hydroxy-Ethyl-Meth-Acrylic) Network in Water

Authors: Yasmina Houda Bendahma, Tewfik Bouchaour, Meriem Merad, Ulrich Maschke

Abstract:

The purpose of this work is to study retention of dye dissolved in distilled water, by an hydrophilic acrylic polymer network. The polymer network considered is Poly (2-hydroxyethyl methacrylate) (PHEMA): it is prepared by photo-polymerization under UV irradiation in the presence of a monomer (HEMA), initiator and an agent cross-linker. PHEMA polymer network obtained can be used in the retention of dye molecules present in the wastewater. The results obtained are interesting in the study of the kinetics of swelling and de-swelling of cross linked polymer networks PHEMA in colored aqueous solutions. The dyes used for retention by the PHEMA networks are eosin Y and Malachite Green, dissolved in distilled water. Theoretical conformational study by a simplified molecular model of system cross linked PHEMA / dye (eosin Y and Malachite Green), is used to simulate the retention phenomenon (or Docking) dye molecules in cavities in nano-domains included in the PHEMA polymer network.

Keywords: dye retention, molecular modeling, photochemically crosslinked polymer network, swelling deswelling, PHEMA, HEMA

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867 Some Trace and Toxic Metal Content of Crude Ethanol Leaf Extract of Globimetula Oreophila (Hook. F) Danser Azadirachta Indica Using Atomic Absorption Spectroscopy

Authors: Dauda G., Bila Ha Sani Y. M., Magaji M. G., Musa A. M., Hassan H. S.

Abstract:

Introduction: Globimetula oreophila is a parasitic plant with a known therapeutic value that is widely used in the treatment of various ailments, including malaria, hypertension, cancer, diabetes, epilepsy and as a diuretic agent. Objectives: The present study is aimed at analyzing and documenting the level of trace and toxic metals in the crude ethanol leaf extract of G. oreophila. Methods: After collection and authentication, the leaves were air-dried, mashed into powder, weighed and extracted using aqueous ethanol (70%). The crude extract (0.5g) was digested with HNO₃: HCl (3:1); then heated to 2000C and analyzed for its metal content by atomic absorption spectroscopy (AAS). Results: Fe had the highest concentration (32.73mg/kg), while Pb was not detected. The concentrations of Co, Cu, Ni, Zn and Cd detected were 5.97, 10.8, 8.01 and 0.9mg/kg, respectively. The concentration of Cd, Fe and Ni were above the permissible limit of FAO/WHO. Conclusion: The results also show that the analyzed plant is a beneficial source of appropriate and essential trace metals. However, the leaf of G. oreophila in the present study was probably unsafe for long-term use because of the level of Fe, Ni, and Cd concentration.

Keywords: Globimetula oreophila, minerals, trace element, crude extract

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866 Developing a Set of Primers Targeting Chondroitin Ac Lyase Gene for Specific and Sensitive Detection of Flavobacterium Columnare, a Causative Agent of Freshwater Columnaris

Authors: Mahmoud Mabrok, Channarong Rodkhum

Abstract:

Flavobacterium columanre is one of the devastating pathogen that causes noticeable economic losses in freshwater cultured fish. Like other filamentous bacteria, F. columanre tends to aggregate and fluctuate to all kind of media, thus revealing obstacles in recognition of its colonies. Since the molecular typing is the only fundamental tool for rapid and precise detection of this pathgen. The present study developed a species-specific PCR assay based on cslA unique gene of F. columnare. The cslA gene sequences of 13 F. columnare, strains retrieved from gene bank database, were aligned to identify a conserved homologous segment prior to primers design. The new primers yielded amplicons of 287 bp from F. columnare strains but not from relevant or other pathogens, unlike to other published set that showed no specificity and cross-reactivity with F. indicum. The primers were sensitive and detected as few as 7 CFUs of bacteria and 3 pg of gDNA template. The sensitivity was reduced ten times when using tissue samples. These primers precisely defined all field isolates in a double-blind study, proposing their applicable use for field detection.

Keywords: Columnaris infection, cslA gene, Flavobacterium columnare, PCR

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865 Synthesis of Flower-Like Silver Nanoarchitectures in Special Shapes and Their Applications in Surface-Enhanced Raman Scattering

Authors: Radka Králová, Libor Kvítek, Václav Ranc, Aleš Panáček, Radek Zbořil

Abstract:

Surface–Enhanced Raman Scattering (SERS) is an optical spectroscopic technique with very good potential for sensitive detection of substances. In this research, active substrates with high enhancement were provided. Novel silver particles (nanostructures) with high roughened, flower–like morphology were prepared by reduction of cation complex [Ag(NH3)2]+ in presence of sodium borohydride as reducing agent and stabilized polyacrylic acid. The products were characterized by UV/VIS absorption spectrophotometry. Special shapes of silver particles were determined by scanning electron microscopy (SEM) and transmission electron spectroscopy (TEM). Dispersions of this particle were put on fixed substrate to producing suitable layer for SERS. Adenine was applied as basic substance whose effect of enhancement on the layer of silver nanostructures was studied. By comparison with our work, the important influence of stabilizers, polyacrylic acid with various molecular weight and concentration, on the transfer of particles and formation of new structure was confirmed.

Keywords: metals, nanostructures, chemical reduction, Raman spectroscopy, optical properties

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864 Investigation of Medicinal Applications of Maclura Pomifera Extract

Authors: Mahdi Asghari Ozma

Abstract:

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

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

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863 Evaluation Rabbit Serum of the Immunodominant Proteins of Mycobacterium avium Paratuberculosis Extracts

Authors: Maryam Hashemi, Nematollah Razmi, Rasool Madani

Abstract:

M. paratuberculosis is a slow growing mycobactin dependent mycobacterial species known to be the causative agent of Johne’s disease in all species of domestic ruminants worldwide. JD is characterized by gradual weight loss; decreased milk production. Excretion of the organism may occur for prolonged periods (1 to 2.5 years) before the onset of clinical disease. In recent years, researchers focus on identification a specific antigen of MAP to use in diagnosis test and preparation of effective vaccine. In this paper, for production of polyclonal antibody against proteins of Mycobacterium avium paratuberculosis cell wall a rabbit immunization at a certain time period with antigen. After immunization of the animal, blood samples were collected from the rabbit for producing enriched serum. Antibodies were purified with ion exchange chromatography. For exact measurement of interaction, western blotting test was used and as it is demonstrated in the study, sharp bands appear in nitrocellulose paper and specific bands were 50 and 150 KD molecular weight. These were indicating immunodominant proteins.

Keywords: immunodominant, paratuberculosis, Western blotting, cell wall proteins, protein purification

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862 A Middle Way Approach for the Conflicts between Death, Impermanence and Non-Self in Buddhist Philosophy

Authors: Ruotian Wang

Abstract:

Since the birth of the Buddha himself more than 2000 years ago, Buddhism has continued to lead many people’s lives. Scholars and Buddhists have contributed to give detailed explanations to all kinds of issues within the structure of Buddhist philosophy to make Buddhism more complete. Different schools have developed, therefore leading to a lot of different branches within Buddhism. Although they all follow what the Buddha himself taught, they still have various explanations to even fundamental issues. As one of the fundamental problems regarding our lives, death is widely discussed in Buddhism. The controversy regarding death is its seemly incompatibility with the idea of non-self and impermanence, which is what I will discuss in this essay. The idea of rebirth is the basic structure of birth and death, which suggests a connection between this life and the next. Therefore, according to common logic, we should tell that there is something that connects each life, an agent that receives the process of rebirth, which is normally known as a soul. In Buddhism, non-self is also an important concept which speaks to the illusion of a self or soul. The idea of rebirth and non-self seems contradicted. Many different schools of Buddhism attempt to resolve such conflicts, but there are logical flaws within the arguments they made. Thus, I raise a better solution: Different from the annihilationist view, non-self in Buddhism speaks only to the illusion of a self in each moment. There is a self that exists as a sum of all our karmas which we can achieve after Nirvana. However, the nature of such a self is still emptiness. There are no agents needed as one rebirth since the whole cycle of rebirth is the self. Then, the contradiction between rebirth and non-self can be resolved.

Keywords: Buddhism, impermanence, non-self, reincarnation

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861 Influence Analysis of Macroeconomic Parameters on Real Estate Price Variation in Taipei, Taiwan

Authors: Li Li, Kai-Hsuan Chu

Abstract:

It is well known that the real estate price depends on a lot of factors. Each house current value is dependent on the location, room number, transportation, living convenience, year and surrounding environments. Although, there are different experienced models for housing agent to estimate the price, it is a case by case study without overall dynamic variation investigation. However, many economic parameters may more or less influence the real estate price variation. Here, the influences of most macroeconomic parameters on real estate price are investigated individually based on least-square scheme and grey correlation strategy. Then those parameters are classified into leading indices, simultaneous indices and laggard indices. In addition, the leading time period is evaluated based on least square method. The important leading and simultaneous indices can be used to establish an artificial intelligent neural network model for real estate price variation prediction. The real estate price variation of Taipei, Taiwan during 2005 ~ 2017 are chosen for this research data analysis and validation. The results show that the proposed method has reasonable prediction function for real estate business reference.

Keywords: real estate price, least-square, grey correlation, macroeconomics

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860 Case Study Analysis for Driver's Company in the Transport Sector with the Help of Data Mining

Authors: Diana Katherine Gonzalez Galindo, David Rolando Suarez Mora

Abstract:

With this study, we used data mining as a new alternative of the solution to evaluate the comments of the customers in order to find a pattern that helps us to determine some behaviors to reduce the deactivation of the partners of the LEVEL app. In one of the greatest business created in the last times, the partners are being affected due to an internal process that compensates the customer for a bad experience, but these comments could be false towards the driver, that’s why we made an investigation to collect information to restructure this process, many partners have been disassociated due to this internal process and many of them refuse the comments given by the customer. The main methodology used in this case study is the observation, we recollect information in real time what gave us the opportunity to see the most common issues to get the most accurate solution. With this new process helped by data mining, we could get a prediction based on the behaviors of the customer and some basic data recollected such as the age, the gender, and others; this could help us in future to improve another process. This investigation gives more opportunities to the partner to keep his account active even if the customer writes a message through the app. The term is trying to avoid a recession of drivers in the future offering improving in the processes, at the same time we are in search of stablishing a strategy which benefits both the app’s managers and the associated driver.

Keywords: agent, driver, deactivation, rider

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859 The Next Generation of Mucoadhesive Polymer

Authors: Flavia Laffleur, Andreas Bernkop-Schnürch

Abstract:

Purpose: This study was aimed to investigate preactivated thiomers for their mucoadhesive potential. Methods: Accordingly, chitosan-thioglycolic-mercaptonicotinamide conjugates (chitosan-TGA-MNA) were synthesized by the oxidative S-S coupling of chitosan-thioglycolic acid (chitosan-TGA) with 6-mercaptonicotin amide (MNA). Unmodified chitosan, chitosan-TGA (thiomers) and chitosan-TGA-MNA conjugates were compressed into test discs to investigate cohesive properties, cytotoxicity assays and mucoadhesion studies. Results: Due to the immobilization of MNA, the chitosan-TGA-MNA conjugates exhibit comparatively higher swelling properties and cohesive properties corresponding unmodified chitosan. On the rotating cylinder, discs based on chitosan-TGA-MNA conjugates displayed 3.1-fold improved mucoadhesion time compared to thiolated polymers. Tensile study results were found in good agreement with rotating cylinder results. Moreover, preactivated thiomers showed higher stability. All polymers were found non-toxic over Caco-2 cells. Conclusion: On the basis of achieved results the pre activated thiomeric therapeutic agent seems to represent a promising generation of mucoadhesive polymers which are safe to use for a prolonged residence time to target the mucosa.

Keywords: biomedical application, drug delivery, polymer, thiomer

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858 Solvent Extraction, Spectrophotometric Determination of Antimony(III) from Real Samples and Synthetic Mixtures Using O-Methylphenyl Thiourea as a Sensitive Reagent

Authors: Shashikant R. Kuchekar, Shivaji D. Pulate, Vishwas B. Gaikwad

Abstract:

A simple and selective method is developed for solvent extraction spectrophotometric determination of antimony(III) using O-Methylphenyl Thiourea (OMPT) as a sensitive chromogenic chelating agent. The basis of proposed method is formation of antimony(III)-OMPT complex was extracted with 0.0025 M OMPT in chloroform from aqueous solution of antimony(III) in 1.0 M perchloric acid. The absorbance of this complex was measured at 297 nm against reagent blank. Beer’s law was obeyed up to 15µg mL-1 of antimony(III). The Molar absorptivity and Sandell’s sensitivity of the antimony(III)-OMPT complex in chloroform are 16.6730 × 103 L mol-1 cm-1 and 0.00730282 µg cm-2 respectively. The stoichiometry of antimony(III)-OMPT complex was established from slope ratio method, mole ratio method and Job’s continuous variation method was 1:2. The complex was stable for more than 48 h. The interfering effect of various foreign ions was studied and suitable masking agents are used wherever necessary to enhance selectivity of the method. The proposed method is successfully applied for determination of antimony(III) from real samples alloy and synthetic mixtures. Repetition of the method was checked by finding relative standard deviation (RSD) for 10 determinations which was 0.42%.

Keywords: solvent extraction, antimony, spectrophotometry, real sample analysis

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857 Study of Effective Parameters on Mechanical Properties of Toughened PP Compounds in Presence of Biofillers and Blowing Agents

Authors: Koosha Rezaei, Mehdi Moghri bidgoli, Mazyar Khakpour

Abstract:

Wood-plastic composites foam is one of the most used products were the industry today. In this study, composite foam polypropylene in the presence of different biofilers such as Spruce wood, wheat and rice husk as well as 3 different types toughening agents such as polyolefin elastomer, styrene butadiene styrene and styrene-ethylene butadiene styrene, and two types of cause blowing agents azodicarbonamide and sodium bicarbonate was prepared. For improving dispersion of biofilers, in the mixing process we used polypropylene coupling agent grafted with maleic anhydride. Due to the large number of variables, the statistical analysis of response surface to analyze the results of the impact test, tensile modulus and tensile strength and modeling were used. Co-rotating twine extruder was made composite melt mixing method and then to perform mechanical tests using injection molding, respectively.Images from electron microscopy showed cell sandwich structure in composite amply demonstrates.

Keywords: polypropylene, wood plastic composite foam, response surface analysis, morphology, mechanical properties

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856 Myroides Bacteremia: A Case Report

Authors: Jamie Lynn Co, Mary Shiela Ariola-Ramos

Abstract:

Myroides are aerobic, yellow-pigmented, non-motile, non-fermenting gram-negative rods. They are commonly found in the environment such as water and soil. Although found in the environment, Myroides are rare pathogens of humans. Myroides spp. primarily infect immunocompromised patients, often with diabetes mellitus, liver cirrhosis, chronic kidney disease, chronic obstructive pulmonary disease or prolonged corticosteroid therapy. We present a case of a 70-year-old immunocompromised patient with diabetes mellitus, chronic renal failure, diagnosed with sepsis caused by Myroides spp. The primary portal and source of infection were the pustules and boils found on the lower extremities of the patient. Susceptibility testing showed that our isolate was only susceptible to ciprofloxacin and meropenem; and following the treatment, the patient recovered. Myroides continues to be a rare pathogen of humans that is prevalent in our environment. It primarily affects immunocompromised patients such as those with uncontrolled diabetes mellitus, chronic kidney disease, etc. Despite their low virulence, physicians should consider this opportunistic pathogen as possible etiologic agent especially in cases wherein there is lack of response to commonly used antibiotics.

Keywords: bacteremia, immunocompromised, gram negative rods, Myroides

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855 Characteristics of Edible Film Made from Skin and Bone Fish Gelatin, Spotted Oceanic Triggerfish (Canthidermis maculata) and Tilapia Fish (Oreochromis niloticus)

Authors: Normalina Arpi, Fahrizal Fahrizal, Dewi Yunita

Abstract:

Edible films can increase the shelf life of various food products by acting as water, oxygen, and lipid barrier. Fish gelatin as a film-forming agent has unique characteristics but varies depending on fish species. The purpose of this research is to characterize edible film made using skin and bone fish gelatin with the addition of plasticizer. Gelatin of spotted oceanic triggerfish (Canthidermis maculata) and tilapia (Oreochromis niloticus) were used. Glycerol and sorbitol with concentration of 0.25 and 0.5 % were added as a plasticizer. Spotted oceanic triggerfish gelatin with sorbitol resulted film with higher tensile strength and oxygen permeability, whereas tilapia gelatin with glycerol produced an edible film with higher elongation and water vapor permeability. The edible film made of spotted oceanic triggerfish gelatin and 0.25% sorbitol had the best characteristics.

Keywords: edible film, fish gelatin , glycerol, sorbitol

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854 ¹⁸F-FDG PET/CT Impact on Staging of Pancreatic Cancer

Authors: Jiri Kysucan, Dusan Klos, Katherine Vomackova, Pavel Koranda, Martin Lovecek, Cestmir Neoral, Roman Havlik

Abstract:

Aim: The prognosis of patients with pancreatic cancer is poor. The median of survival after establishing diagnosis is 3-11 months without surgical treatment, 13-20 months with surgical treatment depending on the disease stage, 5-year survival is less than 5%. Radical surgical resection remains the only hope of curing the disease. Early diagnosis with valid establishment of tumor resectability is, therefore, the most important aim for patients with pancreatic cancer. The aim of the work is to evaluate the contribution and define the role of 18F-FDG PET/CT in preoperative staging. Material and Methods: In 195 patients (103 males, 92 females, median age 66,7 years, 32-88 years) with a suspect pancreatic lesion, as part of the standard preoperative staging, in addition to standard examination methods (ultrasonography, contrast spiral CT, endoscopic ultrasonography, endoscopic ultrasonographic biopsy), a hybrid 18F-FDG PET/CT was performed. All PET/CT findings were subsequently compared with standard staging (CT, EUS, EUS FNA), with peroperative findings and definitive histology in the operated patients as reference standards. Interpretation defined the extent of the tumor according to TNM classification. Limitations of resectability were local advancement (T4) and presence of distant metastases (M1). Results: PET/CT was performed in a total of 195 patients with a suspect pancreatic lesion. In 153 patients, pancreatic carcinoma was confirmed and of these patients, 72 were not indicated for radical surgical procedure due to local inoperability or generalization of the disease. The sensitivity of PET/CT in detecting the primary lesion was 92.2%, specificity was 90.5%. A false negative finding in 12 patients, a false positive finding was seen in 4 cases, positive predictive value (PPV) 97.2%, negative predictive value (NPV) 76,0%. In evaluating regional lymph nodes, sensitivity was 51.9%, specificity 58.3%, PPV 58,3%, NPV 51.9%. In detecting distant metastases, PET/CT reached a sensitivity of 82.8%, specificity was 97.8%, PPV 96.9%, NPV 87.0%. PET/CT found distant metastases in 12 patients, which were not detected by standard methods. In 15 patients (15.6%) with potentially radically resectable findings, the procedure was contraindicated based on PET/CT findings and the treatment strategy was changed. Conclusion: PET/CT is a highly sensitive and specific method useful in preoperative staging of pancreatic cancer. It improves the selection of patients for radical surgical procedures, who can benefit from it and decreases the number of incorrectly indicated operations.

Keywords: cancer, PET/CT, staging, surgery

Procedia PDF Downloads 247