Search results for: bacterial composition

Authors: Maryam Kiani, Xiaoqin Tian, Yu Du, Abdul Basit Kiani

Abstract:

Zn-doped MgFe₂O₄ nanoparticles (ZMFO) (Zn=0.0, 0.2, 0.35, 0.5,) were prepared by Co-precipitation synthesis route. Structural and morphological analysis confirmed the formation of spinel cubic nanostructure by X-Ray diffraction (XRD) data shows high reactive surface area owing to a small average particle size of about 14 nm, which greatly influences the gas sensing mechanism. The gas sensing property of ZMFO for several gases was obtained by measuring the resistance as a function of different factors, like composition and response time in air and in the presence of gas. The sensitivity of spinel ferrite to gases CO₂, O₂, and O₂ at room temperature has been compared. The nanostructured ZMFO exhibited high sensitivity in the order of CO₂>O₂ and showed a good response time of (~1min) to CO₂, demonstrating that this expanse of research can be used in the field of gas sensors devising high sensitivity and good selectivity at 25°C.

Keywords: MgFe₂O₄ nanoparticles, hydrothermal synthesis, gas sensing properties, XRD

Procedia PDF Downloads 89

Authors: M. Chňapek, M. Tomka, R. Peroutková, Z. Gálová

Abstract:

Processes of plant breeding, testing and licensing of new varieties, patent protection in seed production, relations in trade and protection of copyright are dependent on identification, differentiation and characterization of plant genotypes. Therefore, we focused our research on utilization of wheat storage proteins as genetic markers suitable not only for differentiation of individual genotypes, but also for identification and characterization of their considerable properties. We analyzed a collection of 102 genotypes of bread wheat (Triticum aestivum L.), 41 genotypes of spelt wheat (Triticum spelta L.), and 35 genotypes of durum wheat (Triticum durum Desf.), in this study. Our results show, that genotypes of bread wheat and durum wheat were homogenous and single line, but spelt wheat genotypes were heterogenous. We observed variability of HMW-GS composition according to environmental factors and level of breeding and predict technological quality on the basis of Glu-score calculation.

Keywords: genotype identification, HMW-GS, wheat quality, polymorphism

Procedia PDF Downloads 443

Authors: Zoja Raud, Valery Vodovozov

Abstract:

The paper focuses on the distance laboratory organisation for training the electrical engineering staff and students in the fields of electrical drive and power electronics. To support online knowledge acquisition and professional enhancement, new challenges in remote education based on an active learning approach with self-assessment have been emerged by the authors. Following the literature review and explanation of the improved assessment methodology, the concept and technological basis of the labs arrangement are presented. To decrease the gap between the distance study of the up-to-date equipment and other educational activities in electrical engineering, the improvements in the following-up the learners’ progress and feedback composition are introduced. An authoring methodology that helps to personalise knowledge acquisition and enlarge Web-based possibilities is described. Educational management based on self-assessment is discussed.

Keywords: advanced training, active learning, distance learning, electrical engineering, remote laboratory, self-assessment

Procedia PDF Downloads 307

Authors: D. M. Bassuney, W. A. Ibrahim, Medhat A. E. Moustafa

Abstract:

Appropriate start-up of an anaerobic baffled reactor (ABR) is considered to be the most delicate and important issue in the anaerobic process, and depends on several factors such as wastewater composition, reactor configuration, inoculum and operating conditions. In this work, the start-up performance of an ABR with working volume of 30 liters, fed continuously with synthetic food industrial wastewater along with semi-batch study to measure the methangenic activity by specific methanogenic activity (SMA) test were carried out at various organic loading rates (OLRs) to determine the best OLR used to start up the reactor. The comparison was based on COD removal efficiencies, start-up time, pH stability and methane production. An OLR of 1.8 Kg COD/m3d (5400 gCOD/m3 and 3 days HRT) showed best overall performance with COD removal efficiency of 94.44% after four days from the feeding and methane production of 3802 ml/L with an overall SMA of 0.36 gCH4-COD/gVS.d

Keywords: anaerobic baffled reactor, anaerobic reactor start-up, food industrial wastewater, specific methanogenic activity

Procedia PDF Downloads 370

Authors: Evgeniia Shavrina, Yan Zeng, Boo Cheong Khoo, Vinh-Tan Nguyen

Abstract:

The present paper is aimed at providing a review of error sources in cryogenic metering by Coriolis flowmeters (CFMs). Whereas these flowmeters allow accurate water metering, high uncertainty and low repeatability are commonly observed at cryogenic fluid metering, which is often necessary for effective renewable energy production and storage. The sources of these issues might be classified as general and cryogenic specific challenges. A conducted analysis of experimental and theoretical studies shows that material behaviour at cryogenic temperatures, composition variety, and multiphase presence are the most significant cryogenic challenges. At the same time, pipeline diameter limitation, ambient vibration impact, and drawbacks of the installation may be highlighted as the most important general challenges of cryogenic metering by CFM. Finally, the techniques, which mitigate the impact of these challenges are reviewed, and future development direction is indicated.

Keywords: Coriolis flowmeter, cryogenic, multicomponent flow, multiphase flow

Procedia PDF Downloads 132

Authors: Binyamien Rasoul

Abstract:

Portland cement is one of the most widely used construction materials in the world today; however, manufacture of ordinary Portland cement (OPC) emission significant amount of CO2 resulting environmental impact. On the other hand, rice husk ash (RHA), which is produce as by product material is generally considered to be an environmental issue as a waste material. This material (RHA) consists of non-crystalline silicon dioxide with high specific surface area and high pozzolanic reactivity. These RHA properties can demonstrate a significant influence in improving the mechanical and durability properties of mortar and concrete. Furthermore, rice husk ash can provide a cost effective and give concrete more sustainability. In this paper, chemical composition, reactive silica and fineness effect was assessed by examining five different types of RHA. Mortars and concrete specimens were molded with 5% to 50% of ash, replacing the Portland cement, and measured their compressive and tensile strength behavior. Beyond it, another two parameters had been considered: the durability of concrete blended RHA, and effect of temperature on the transformed of amorphous structure to crystalline form. To obtain the rice husk ash properties, these different types were subjected to X-Ray fluorescence to determine the chemical composition, while pozzolanic activity obtained by using X-Ray diffraction test. On the other hand, finesses and specific surface area were obtained by used Malvern Mastersizer 2000 test. The measured parameters properties of fresh mortar and concrete obtained by used flow table and slump test. While, for hardened mortar and concrete the compressive and tensile strength determined pulse the chloride ions penetration for concrete using NT Build 492 (Nord Test) – non-steady state migration test (RMT Test). The obtained test results indicated that RHA can be used as a cement replacement material in concrete with considerable proportion up to 50% percentages without compromising concrete strength. The use of RHA in the concrete as blending materials improved the different characteristics of the concrete product. The paper concludes that to exhibits a good compressive strength of OPC mortar or concrete with increase RHA replacement ratio rice husk ash should be consist of high silica content with high pozzolanic activity. Furthermore, with high amount of carbon content (12%) could be improve the strength of concrete when the silica structure is totally amorphous. As well RHA with high amount of crystalline form (25%) can be used as cement replacement when the silica content over 90%. The workability and strength of concrete increased by used of superplasticizer and it depends on the silica structure and carbon content. This study therefore is an investigation of the effect of partially replacing Ordinary Portland cement (OPC) with Rice hush Ash (RHA) on the mechanical properties and durability of concrete. This paper gives satisfactory results to use RHA in sustainable construction in order to reduce the carbon footprint associated with cement industry.

Keywords: OPC, ordinary Portland cement, RHA rice husk ash, W/B water to binder ratio, CO2, carbon dioxide

Procedia PDF Downloads 174

Authors: Mehak Munjal, Raj Kishore Sharma, Gurmeet Singh

Abstract:

Microbial Fuel Cells (MFCs) are an alternative sustainable approach that utilize bacteria present in waste water as a bio-catalyst for the production of energy. It is a promising growing technology with minimal requirement for chemical supplements. Here electrode material plays a vital role in its performance. The present study represents CoFe2O4 spinel as a novel anode material in the MFC. It not only improve the bacterial metabolics but also enhance the power output. Generally, biocompatible conductive carbon paper/cloth, graphite and stainless steel are utilised as anode in MFCs. However, these materials lack electrochemical activity for anodic microbial reaction. Therefore, we developed CoFe2O4 on graphite sheet which enhanced the anodic charge transfer process. Redox pair in CoFe2O4 helped in improvement of extracellular electron transfer, thereby enhancing the performance. The physical characterizations (FT-IR, XRD, Raman) and electrochemical measurements demonstrate the strong interaction with E.coli bacteria and thus providing an excellent power density i.e. 1850 mW/m2 .The maximum anode half -cell potential is measured to be 0.65V. Therefore, use of noble metal free anodic material further decrease the cost and the long term cell stability makes it an effective material for practical applications.

Keywords: microbial fuel cell, cobalt ferrite, E. coli, bioelectricity

Procedia PDF Downloads 118

Authors: Tatiana A. Dolenko, Sergey A. Burikov, Alexander O. Efitorov, Sergey A. Dolenko

Abstract:

In this study, a comparative analysis of the approaches associated with the use of neural network algorithms for effective solution of a complex inverse problem – the problem of identifying and determining the individual concentrations of inorganic salts in multicomponent aqueous solutions by the spectra of Raman scattering of light – is performed. It is shown that application of artificial neural networks provides the average accuracy of determination of concentration of each salt no worse than 0.025 M. The results of comparative analysis of input data compression methods are presented. It is demonstrated that use of uniform aggregation of input features allows decreasing the error of determination of individual concentrations of components by 16-18% on the average.

Keywords: inverse problems, multi-component solutions, neural networks, Raman spectroscopy

Procedia PDF Downloads 504

Authors: Mustafa Abu Ghalia, Yaser Dahman

Abstract:

A new class of polyurethane (PU) reinforced with green bacterial cellulose nanofibers (BC) were prepared using a solvent casting method, with the goal of fabricating green nanocomposites. Four series classes of BC (1, 2.5, 5, and 10 wt%) were reinforced into PU matrices via BC surface modification and subsequently BC-grafted into PU throughout silane coupling agent to improve BC dispersion and its interfacial interaction. The experiment results from the tensile tester were evaluated according to the response surface method (RSM) for optimizing the impacts of variable parameters, pore size, porosity, and BC contents on the mechanical properties. The compressive strength for PU-5 BC wt% was about 9.8 MPa, and decrease when being generated prosperity to recorded at 4.9 MPa. Nielson model was applied to investigate the BC stress concentration on the PU matrices. Likewise, krenche and Hapli-Tasi model were employed to evaluate the BC nanofiber reinforcement potential and BC orientation into PU matrices. The analysis of variance (ANOVA) demonstrated that only BC loading has a significant effect in increases tensile strength, young’s modulus, and a flexural modulus of the PU-BC nanocomposites. The optimal factors of the variables experiment confirmed to be 5 wt% for BC, 230 for pore size, and 80 % for porosity. Scanning electron microscopy (SEM) micrographs showed that the uniform distribution of nanofibers in the PU matrices with the addition of BC 5 wt %. Hydrolytic degradation revealed that the weight loss in PU-BC scaffold is higher than PU-BC wt %.

Keywords: polyurethane scaffold, mechanical properties, tissue engineering, polyurethane

Procedia PDF Downloads 191

Authors: K. Chouchane, R. Mehdaoui, A. Atmani, A. Merati

Abstract:

A Co-P layer was coated onto steel substrate using electroless plating method in alkaline media. Three temperatures were tested 70, 80 and 90 °C. Sodium hypophosphite was used as a reducer. The influence of addition of boric acid in the bath on deposits properties was studied. Different techniques such as scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and hardness measures were employed to characterize the morphology, composition and the structural properties of the resulting films. The corrosion properties of the prepared coatings were tested in 3% NaCl media, by means of current-potential curves, potential transients. The results showed that the thickness increase with increasing of bath temperature. The addition of boric acid don’t affect the thickness but has an influence on hardness. In fact, the hardness increases from 500 to 700Hv for the temperature of 90°C. The corrosion resistance is improved for all prepared layers.

Keywords: cobalt deposits, corrosion, electroless deposition, hardness

Procedia PDF Downloads 190

Authors: Malkhaz Jokhadze, Vakhtang Mshvildadze, Levan Makaradze, Ekaterine Mosidze, Salome Barbaqadze, Mariam Murtazashvili, Dali Berashvili, Koba sivsivadze, Lasha Bakuridze, Aliosha Bakuridze

Abstract:

Essential oils are one of the most important groups of biologically active substances present in plants. Due to the chemical diversity of components, essential oils and their preparations have a wide spectrum of pharmacological action. They have bactericidal, antiviral, fungicidal, antiprotozoal, anti-inflammatory, spasmolytic, sedative and other activities. They are expectorant, spasmolytic, sedative, hypotensive, secretion enhancing, antioxidant remedies. Based on preliminary pharmacological studies, we have developed a formulation called “Phytobiotic” containing essential oils, a feed additive for poultry as an alternative to antibiotics. Phytobiotic is a water-soluble powder containing a composition of essential oils of thyme, clary, monarda and auxiliary substances: dry extract of liquorice and inhalation lactose. On this stage of research, the goal was to study the chemical composition of provided phytobiotic, identify the main substances and determine their quantity, investigate the biological activity of phytobiotic through in vitro and in vivo studies. Using gas chromatography-mass spectrometry, 38 components were identified in phytobiotic, representing acyclic-, monocyclic-, bicyclic-, and sesquiterpenes. Together with identification of main active substances, their quantitative content was determined, including acyclic terpene alcohol β-linalool, acyclic terpene ketone linalyl acetate, monocyclic terpenes: D-limonene and γ-terpinene, monocyclic aromatic terpene thymol. Provided phytobiotic has pronounced and at the same time broad spectrum of antibacterial activity. In the cell model, phytobiotic showed weak antioxidant activity, and it was stronger in the ORAC (chemical model) tests. Meanwhile anti-inflammatory activity was also observed. When fowls were supplied feed enriched with phytobiotic, it was observed that gained weight of the chickens in the experimental group exceeded the same data for the control group during the entire period of the experiment. The survival rate of broilers in the experimental group during the growth period was 98% compared to -94% in the control group. As a result of conducted researches probable four different mechanisms which are important for the action of phytobiotics were identified: sensory, metabolic, antioxidant and antibacterial action. General toxic, possible local irritant and allergenic effects of phytobiotic were also investigated. Performed assays proved that formulation is safe.

Keywords: clary, essential oils, monarda, poultry, phytobiotics, thyme

Procedia PDF Downloads 153

Authors: Gina Zavaleta-Espejo, Segundo R. Jáuregui-Rosas, Fanny V. Samanamud-Moreno, José Saldaña Jiménez, Anibal Felix-Quintero, Víctor Montero-Del Aguila, Elsi Mejía-Uriarte

Abstract:

Vicugnapacos "alpaca" fabrics are considered special for their finesse, and the garments in the textile market are very luxurious. It has many special characteristics such as antiallergic, soft, hygroscopic, among others. In this sense, the research aimed to evaluate the antimicrobial activity of alpaca fabrics functionalized with silver nanoparticles on the bacteria Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923. For the functionalization of the fabrics, AgNO3 and different concentrations of trisodium citrate (TSC) 2, 6, and 10 mg. Tissue characterization was performed using Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The determination of the antimicrobial activity of the alpaca tissues was made by the Kirby-Bauer method with alpaca tissue discs functionalized with silver nanoparticles, an experimental design was made in completely randomized blocks with three treatments and a negative control with three repetitions. The results showed that inhibition halos were formed for both bacteria, therefore, the functionalized tissues have a high antimicrobial activity, whose mechanism of action is attributed to the free radicals (ROS) generated by the nanoparticles that cause oxidative damage to the bacteria. proteins and lipids of the bacterial cell wall.

Keywords: antimicrobial, animal fibers, fabrics, functionalization, trisodium citrate

Procedia PDF Downloads 117

Authors: R. Sharma, J. K. Bhatnagar, Poonam, R. C. Sharma

Abstract:

Metal–air batteries have been designed and developed as an essential source of electric power to propel automobiles, make electronic equipment functional, and use them as the source of power in remote areas and space. High energy and power density, lightweight, easy recharge capabilities, and low cost are essential features of these batteries. Both primary and rechargeable magnesium air batteries are highly promising. Our focus will be on the basics of electrode reaction kinetics of Mg–air cell in this paper. Design and development of Mg or Mg alloys as anode materials, design and composition of air cathode, and promising electrolytes for Mg–air batteries have been reviewed. A brief note on the possible and proposed improvements in design and functionality is also incorporated. This article may serve as the primary and premier document in the critical research area of Mg-air battery systems.

Keywords: air cathode, battery design, magnesium air battery, magnesium anode, rechargeable magnesium air battery

Procedia PDF Downloads 211

Authors: Agnieszka Markowska-Radomska, Ewa Dluska

Abstract:

Maintaining a bioactive substances dense diet is important for the elderly, especially to prevent diseases and to support healthy ageing. Adequate bioactive substances intake can reduce the risk of developing chronic diseases (e.g. cardiovascular, osteoporosis, neurodegenerative syndromes, diseases of the oral cavity, gastrointestinal (GI) disorders, diabetes, and cancer). This can be achieved by introducing a comprehensive supplementation of components necessary for the proper functioning of the ageing body. The paper proposes the multiple emulsions of the W1/O/W2 (water-in-oil-in-water) type as carriers for effective co-encapsulation and co-delivery of bioactive substances in supplementation of the elderly. Multiple emulsions are complex structured systems ("drops in drops"). The functional structure of the W1/O/W2 emulsion enables (i) incorporation of one or more bioactive components (lipophilic and hydrophilic); (ii) enhancement of stability and bioavailability of encapsulated substances; (iii) prevention of interactions between substances, as well as with the external environment, delivery to a specific location; and (iv) release in a controlled manner. The multiple emulsions were prepared by a one-step method in the Couette-Taylor flow (CTF) contactor in a continuous manner. In general, a two-step emulsification process is used to obtain multiple emulsions. The paper contains a proposal of emulsion functionalization by introducing pH-responsive biopolymer—carboxymethylcellulose sodium salt (CMC-Na) to the external phase, which made it possible to achieve a release of components controlled by the pH of the gastrointestinal environment. The membrane phase of emulsions was soybean oil. The W1/O/W2 emulsions were evaluated for their characteristics (drops size/drop size distribution, volume packing fraction), encapsulation efficiency and stability during storage (to 30 days) at 4ºC and 25ºC. Also, the in vitro multi-substance co-release process were investigated in a simulated gastrointestinal environment (different pH and composition of release medium). Three groups of stable multiple emulsions were obtained: emulsions I with co-encapsulated vitamins B12, B6 and resveratrol; emulsions II with vitamin A and β-carotene; and emulsions III with vitamins C, E and D3. The substances were encapsulated in the appropriate emulsion phases depending on the solubility. For all emulsions, high encapsulation efficience (over 95%) and high volume packing fraction of internal droplets (0.54-0.76) were reached. In addition, due to the presence of a polymer (CMC-Na) with adhesive properties, high encapsulation stability during emulsions storage were achieved. The co-release study of encapsulated bioactive substances confirmed the possibility to modify the release profiles. It was found that the releasing process can be controlled through the composition, structure, physicochemical parameters of emulsions and pH of the release medium. The results showed that the obtained multiple emulsions might be used as potential liquid complex carriers for controlled/modified/site-specific co-delivery of bioactive substances in dietary supplementation in the elderly.

Keywords: bioactive substance co-release, co-encapsulation, elderly supplementation, multiple emulsion

Procedia PDF Downloads 181

Authors: R. Fegas, S. Zerkout, S. Taberkokt, M. Righezza

Abstract:

The present work demonstrate the potential of Betacyclodextrine (BCD) for the chiral analysis of a drug .Various separation mechanisms were applied and several parameters affecting the separation were studied, including the type and concentration of chiral selector, and pH of buffer. A simple and sensitive high-performance liquid chromatography (HPLC) method was developed as an assay for fexofenadine enantiomers in pharmaceutical preparation. Fexofenadine enantiomers were separated using a mobile phase of 0.25mM NaH2PO4–acetonitrile (65:35, v/v) – Betacyclodextrine on achiral phenyl-urea column at a flow rate of 1ml/min and measurement at 220nm. The chiral mechanism of separation was mainly based on specific interaction between the solute and the stationary phase. The retention was directly controlled by mobile phase composition but not the selectivity which results of the two mechanisms, electrostatic interactions and partition mechanism.

Keywords: fexofenadine enantiomer, HPLC, achiral phenyl-urea column

Procedia PDF Downloads 444

Authors: Myriam Ben Said, Dhekra Trabelsi, Faouzi Achouri, Marwa Ben Saad, Latifa Bousselmi, Ahmed Ghrabi

Abstract:

This present study suggests the use of biological and natural bactericide, cheap, safe to handle, natural, environmentally benign agents to enhance the conventional wastewater treatment process. In the same sense, to highlight the enhancement of wastewater photocatalytic treatability, we were used virulent bacteriophage(s) and essential oils (EOs). The pre-phago-treatment of wastewater with lytic phage(s), leads to a decrease in bacterial density and, consequently, limits the establishment of intercellular communication (QS), thus preventing biofilm formation and inhibiting the expression of other virulence factors after photocatalysis. Moreover, to increase the photocatalytic efficiency, we were added to the secondary treated wastewater 1/1000 (w/v) of EO of thyme (T. vulgaris). This EO showed in vitro an anti-biofilm activity through the inhibition of plonctonic cell mobility and their attachment on an inert surface and also the deterioration of the sessile structure. The presence of photoactivatable molecules (photosensitizes) in this type of oil allows the optimization of photocatalytic efficiency without hazards relayed to dyes and chemicals reagent. The use of ‘biological and natural tools’ in combination with usual water treatment process can be considered as a safety procedure to reduce and/or to prevent the recontamination of treated water and also to prevent the re-expression of virulent factors by pathogenic bacteria such as biofilm formation with friendly processes.

Keywords: biofilm, essential oil, optimization, phage, photocatalysis, wastewater

Procedia PDF Downloads 131

Authors: M. Shopska, D. Paneva, G. Kadinov, Z. Cherkezova-Zheleva, I. Mitov

Abstract:

The iron containing materials are used as catalysts in different processes. The chemical methods of their synthesis use toxic and expensive chemicals; sophisticated devices; energy consumption processes that raise their cost. Besides, dangerous waste products are formed. At present time such syntheses are out of date and wasteless technologies are indispensable. The bioinspired technologies are consistent with the ecological requirements. Different microorganisms participate in the biomineralization of the iron and some phytochemicals are involved, too. The methods for biogenic production of iron containing materials are clean, simple, nontoxic, realized at ambient temperature and pressure, cheaper. The biogenic iron materials embrace different iron compounds. Due to their origin these substances are nanosized, amorphous or poorly crystalline, porous and have number of useful properties like SPM, high magnetism, low toxicity, biocompatibility, absorption of microwaves, high surface area/volume ratio, active sites on the surface with unusual coordination that distinguish them from the bulk materials. The biogenic iron materials are applied in the heterogeneous catalysis in different roles - precursor, active component, support, immobilizer. The application of biogenic iron oxide materials gives rise to increased catalytic activity in comparison with those of abiotic origin. In our study we investigated the catalytic behavior of biomasses obtained by cultivation of Leptothrix bacteria in three nutrition media – Adler, Fedorov, and Lieske. The biomass composition was studied by Moessbauer spectroscopy and transmission IRS. Catalytic experiments on CO oxidation were carried out using in situ DRIFTS. Our results showed that: i) the used biomasses contain α-FeOOH, γ-FeOOH, γ-Fe2O3 in different ratios; ii) the biomass formed in Adler medium contains γ-FeOOH as main phase. The CO conversion was about 50% as evaluated by decreased integrated band intensity in the gas mixture spectra during the reaction. The main phase in the spent sample is γ-Fe2O3; iii) the biomass formed in Lieske medium contains α-FeOOH. The CO conversion was about 20%. The main phase in the spent sample is α-Fe2O3; iv) the biomass formed in Fedorov medium contains γ-Fe2O3 as main phase. CO conversion in the test reaction was about 19%. The results showed that the catalytic activity up to 200°C resulted predominantly from α-FeOOH and γ-FeOOH. The catalytic activity at temperatures higher than 200°C was due to the formation of γ-Fe2O3. The oxyhydroxides, which are the principal compounds in the biomass, have low catalytic activity in the used reaction; the maghemite has relatively good catalytic activity; the hematite has activity commensurate with that of the oxyhydroxides. Moreover it can be affirmed that catalytic activity is inherent in maghemite, which is obtained by transformation of the biogenic lepidocrocite, i.e. it has biogenic precursor.

Keywords: nanosized biogenic iron compounds, catalytic behavior in reaction of CO oxidation, in situ DRIFTS, Moessbauer spectroscopy

Procedia PDF Downloads 355

Authors: Benguerine Zohra, Merzak Siham, Bouziane Cheimaa, Si Tayeb Fatima, Jou Siham, Belkessam

Abstract:

Introduction: Antibiotics, widely produced and consumed in large quantities, have proven problematic due to various types of side effects. The development of bacterial resistance to currently available antibiotics has made the search for new antibacterial agents necessary. One alternative strategy to combat antibiotic-resistant bacteria is the use of natural antimicrobial substances such as plant extracts. The objective of this study is to provide an overview of the antibacterial effects of a plant native to the Middle East and Mediterranean regions, Salvia officinalis (sage). Materials and Methods: This review article was conducted by searching studies in the PubMed, Scopus, JSTOR, and SpringerLink databases. The search terms were "Salvia officinalis L." and "antibacterial effects." Only studies that met our inclusion criteria (in English, antibacterial effects of Salvia officinalis L., and primarily dating from 2012 to 2023) were accepted for further review. Results and Discussion: The initial search strategy identified approximately 78 references, with only 13 articles included in this review. The synthesis of the articles revealed that several data sources confirm the antimicrobial effects of S. officinalis. Its essential oil and alcoholic extract exhibit strong bactericidal and bacteriostatic effects against both Gram-positive and Gram-negative bacteria. Conclusion: The significant value of the extract, oil, and leaves of S. officinalis calls for further studies on the other useful and unknown properties of this multi-purpose plant.

Keywords: salvia officinalis, literature review, antibacterial, effects

Procedia PDF Downloads 18

Authors: N. Belas, O. Belaribi, S. Aggoun, K. Bendani, N. Bouhamou, A. Mebrouki

Abstract:

This experimental work is a part of a long research on the valorization of the dam dredged sediments issued from Fergoug Dam (Mascara-West Algeria). These sediments have to be subjected to thermal treatment to become reactive with the cement and thus to obtain an artificial pozzolana. It is therefore a question of developing the calcined mud as substitutable material in part to the cement used in the composition of self compacting concrete. The objective of the present work is to highlight its influence on the behavior of self compacting concrete compared to that of the natural pozzolana and this, in fresh and hardened states. The study is being conducted on three SCC, the first using 20% in volume of natural pozzolana, the second with 20 % of calcined mud and the third for the sake of comparison is made with cement only. The first results showed the possibility of obtaining SCC with calcined mud complying with the AFGC recommendations having a good mechanical behavior which makes interesting its development as construction materials.

Keywords: dam, fresh state, hardened state mud, sediments, self compacting concrete, valorization

Procedia PDF Downloads 488

Authors: Ganga Sagar Bhattarai, Swastika Gurung

Abstract:

Antibiotics were being misused in both humans and animals, which led to the development of multidrug-resistant microorganisms. Antibiotic abuse is likely rampant among goats, cows, and buffaloes in order to boost growth and reduce production losses. The aim of this study is to know the multidrug resistance (MDR) bacteria in goats, cows, and buffaloes. Out of 68 samples that were examined, S. aureus, Bacillus spp., E. coli, Shigella spp., Klebsiella spp., S. epidremidis, and Salmonella spp. were isolated. S. aureus was the highest isolated bacteria (91.17%), Bacillus spp. (61.76%), E. coli (48.52%), Shigella spp. (22.05%), Klebsiella spp. (17.64%), S. epidermidis (13.23%), and the Salmonella spp. (7.35%). Salmonella spp. and E. coli showed multidrug resistance to at least four antibiotics, including Amoxicillin, Tetracycline, Piperacillin, and Ciprofloxacin, in Salmonella and to at least three antibiotics, including Amoxicillin, Tetracycline, and Nalidic acid. The highest resistance bacteria Salmonella spp. showed (57.14%) E. coli and Bacillus spp. showed (42.85%) S. aureus, S. epidermidis, and Shigella spp. showed (28.57%), and Klebsiella spp. showed (14.28%). This study showed that antibiotic-resistant bacteria with high levels of Amoxicillin, Penicillin, and Tetracycline resistance are present in healthy farm animals such as goats, cows, and buffaloes. Options for antibiotic therapy in both humans and animals will likely be limited as a result. The use, distribution, storage, and sale of antibiotics in veterinary practices must consequently be under strict control.

Keywords: multidrug resistance, multidrug resistance bacteria, susceptibility testing, bacterial infections

Procedia PDF Downloads 73

Authors: Jaruwan Chutrtong

Abstract:

Yoghurt is a fermented milk product. The process of making yogurt involves fermenting milk with live and active bacterial cultures by adding bacteria directly to the dairy product. It is usually made with a culture of Lactobacillus sp. (L. acidophilus or L. bulgaricus) and Streptococcus thermophilus. Many people like to eat it plain or flavored and it's also use as ingredient in many dishes. Yogurt is rich in nutrients including the microorganism which have important role in balancing the digestion and absorption of the boy.Consumers will benefit from lactic acid bacteria more or less depending on the amount of bacteria that lives in yogurt while eating. When purchasing yogurt, consumers should always check the label for live cultures. Yoghurt must keep in refrigerator at 4°C for up to ten days. After this amount of time, the cultures often become weak. This research studied freezing dry yogurt storage by monitoring on the survival of microorganisms when stored at different temperatures. At 300°C, representative room temperature of country in equator zone, number of lactic acid bacteria reduced 4 log cycles in 10 week. At 400°C, representative temperature in summer of country in equator zone, number of lactic acid bacteria also dropped 4 log cycle in 10 week, similar as storage at 300°C. But drying yogurt storage at 400°C couldn’t reformed to be good character yogurt as good as storage at 400°C only 4 week storage too. After 1 month, it couldn’t bring back the yogurt form. So if it is inevitable to keep yogurt powder at a temperature of 40°C, yoghurt is maintained only up to 4 weeks.

Keywords: dynamic, dry yoghurt, storage, temperature

Procedia PDF Downloads 303

Authors: Pierre Y. Matar, Louay S. El Hassanieh, Marleine F. Bayssary

Abstract:

The demolished concrete is a major component of the construction and demolition (C&D) waste. The recycled aggregates obtained by crushing the demolished concrete can be used as a substitute of natural aggregates. Another major C&D waste is the flat glass. This glass can be also recycled and used as an aggregate substitute. The objective of this study is to determine the influence of the use of recycled concrete aggregates and recycled glass on the compressive strength and fire resistance of precast concrete masonry blocks. Tests are carried out on four series of blocks whose compositions include different percentages of recycled aggregates and recycled glass and one series of reference blocks whose composition consists of exclusively natural aggregates. The recycled coarse aggregates and recycled glass have 6.3/12.5 mm fraction and the natural aggregates have 0/6.3 mm fraction; no recycled fine aggregates are included in concrete mixes.

Keywords: compressive strength, precast concrete blocks, recycled aggregates, recycled glass

Procedia PDF Downloads 532

Authors: Thilivhali Emmanuel Tshikalange, Phiwokuhle Mamba

Abstract:

Ten medicinal plants used traditionally in the treatment of sexually transmitted diseases (STDs) and urinary tract infections (UTIs) were selected from an ethnobotanical database developed in Mpumalanga. The plants were investigated for their antimicrobial activity against five bacterial strains (Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Neisseria gonorrhoeae and Staphylococcus aureus) and one fungal strain (Candida albicans). Eight of the plants inhibited the growth of all microorganisms at a concentration range of 0.4 mg/ml to 12.5 mg/ml. Acacia karroo showed the most promising antimicrobial activity, with a minimum inhibitory concentration (MIC) of 0.4 mg/ml on Staphylococcus aureus and 0.8 mg/ml on Neisseria gonorrhoeae. All ten plants were further investigated for their antioxidant activities using the DPPH scavenging method. Acacia karroo and Rhoicissus tridentata subsp. cuneifolia showed good antioxidant activity with IC50 values of 0.83 mg/ml and 0.06 mg/ml, respectively. The toxicity of plants was determined using the XTT reduction method against Vero cells. None of the ten plants showed toxicity on the cells. The obtained results confirmed that Acacia karroo and possibly Rhoicissus tridentata subsp. cuneifolia have the potential of being used as antimicrobial agents in the treatment of STDs and UTIs. These results support and validate traditional use of medicinal plants studied.

Keywords: antimicrobial, antioxidant, Neisseria gonorrhoeae, sexually transmitted diseases

Procedia PDF Downloads 315

Authors: Torchane Lazhar

Abstract:

In this work, our task consists in optimizing the nitriding treatment at low-temperature of the steel 32CrMoV13 by the way of the mixtures of ammonia gas, nitrogen and hydrogen to improve the mechanical properties of the surface (good wear resistance, friction and corrosion), and of the diffusion layer of the nitrogen (good resistance to fatigue and good tenacity with heart). By limiting our work to the pure iron and to the alloys iron-chromium and iron-chrome-carbon, we have studied the various parameters which manage the nitriding: flow rate and composition of the gaseous phase, the interaction chromium-nitrogen and chromium-carbon by the help of experiments of nitriding realized in the laboratory by thermogravimetry. The acquired knowledge have been applied by the mastery of the growth of the combination layer on the diffusion layer in the case of the industrial steel 32CrMoV13.

Keywords: diffusion of nitrogen, gaseous nitriding, layer growth kinetic, steel

Procedia PDF Downloads 393

Authors: Geraldine Giraldo

Abstract:

In the research of advanced materials, ceramics based on KNN are an important topic, especially for multifunctional applications. In this work, the physical, structural, and microstructural properties of the (KNN-CaLi-xSm) system were analyzed by varying the concentration of samarium, which was prepared using the conventional solid-state reaction method by mixing oxides. It was found that the increase in Sm+3 concentration led to higher porosity in the sample and, consequently, a decrease in density, which is attributed to the structural vacancies at the A-sites of the perovskite-type structure of the ceramic system. In the structural analysis, a coexistence of Tetragonal (T) and Orthorhombic (O) phases were observed at different rare-earth ion contents, with a higher content of the T phase at xSm=0.010. Furthermore, the structural changes in the calcined powders at different temperatures were studied using the results of DTA-TG, which allowed for the analysis of the system's composition. It was found that the lowest total decomposition temperature occurred when xSm=0.010 at 770°C.

Keywords: perovskite, piezoelectric, multifunctional, Structure, ceramic

Procedia PDF Downloads 48

Authors: Afsoun Nikravan, Parisa Babaei, Gulen Gullu

Abstract:

We aimed to study the association between house dust endotoxin, β-(1→3)-D-glucan, and asthma in a sample representative of the Turkish population. We analyzed data from 240 participants. The house dust was collected from the homes of 110 asthmatics and 130 control (without asthma) school-aged children (6-11 years old). House dust from the living room and from bedroom floors were analyzed for endotoxin and beta-glucan contents. House dust was analyzed for endotoxin content by the kinetic limulus amoebocyte lysate assay and for β-(1→3)-D-glucan by the inhibition enzyme immunoassay. The parents answered questions regarding potential determinants. We found geometric means 187.5 mg/m² for dust. According to statistical values, the endotoxin geometric mean was 13.86×103 EU/g for the control group and 6.16×103 EU/g for the asthma group. As a result, the amount of bacterial endotoxin was measured at a higher level in the homes of children without asthma. The geometric mean for beta-glucan was 46.52 µg/g and 44.39 µg/g for asthma and control groups, respectively. No associations between asthma and microbial agents were observed in Turkish children. High correlations (r > 0.75) were found between floor dust and endotoxin loads, while endotoxin and β-(1→3)-D-glucan concentrations were not correlated. The type of flooring (hard-surface or textile) was the strongest determinant for loads of floor dust and concentrations of endotoxin. Water damage and dampness at home were determinants of β-(1→3)-D-glucan concentrations. Endotoxin and β-(1→3)-D-glucan concentrations in Turkish house dust might lower than concentrations seen in other European countries.

Keywords: indoor air quality, asthma, microbial pollutants, case-control

Procedia PDF Downloads 101

Authors: Jachin Pousson, Valdis Bernhofs

Abstract:

Applications of the binaural sound experience are wide-ranged. This paper focuses on the interaction between binaural tones and human emotion with an aim to apply the resulting knowledge artistically. For the purpose of this study, binaural music is defined as musical arrangements of sound which are made of combinations of binaural difference tones. Here, the term ‘binaural difference tone’ refers to the pulsating tone heard within the brain which results from listening to slightly differing audio frequencies or pure pitches in each ear. The frequency or tempo of the pulsations is the sum of the precise difference between the frequencies two tones and is measured in beats per second. Polyrhythmic pulsations that can be heard within combinations of these differences tones have shown to be able to entrain or tune brainwave patterns to frequencies which have been linked to mental states which can be characterized by different levels of attention and mood.

Keywords: binaural auditory pulsations, brainwave entrainment, emotion, music composition

Procedia PDF Downloads 155

Authors: Filipe Cardoso de Oliveira, Lino Marcos da Silva, Ademar Nogueira do Nascimento, Cristiano Hora de Oliveira Fontes

Abstract:

This article presents a mathematical formulation for the production Break-Even Point problem in a non-homogeneous system. The optimization problem aims to obtain the composition of the best product mix in a non-homogeneous industrial plant, with the lowest cost until the breakeven point is reached. The problem constraints represent real limitations of a generic non-homogeneous industrial plant for n different products. The proposed model is able to solve the equilibrium point problem simultaneously for all products, unlike the existing approaches that propose a resolution in a sequential way, considering each product in isolation and providing a sub-optimal solution to the problem. The results indicate that the product mix found through the proposed model has economical advantages over the traditional approach used.

Keywords: branch and bound, break-even point, non-homogeneous production system, integer linear programming, management accounting

Procedia PDF Downloads 188

Authors: O. R. Raimi, A. Lateef

Abstract:

Inoculum developments of A. niger were used for inoculation of medium for submerged fermentation and solid state fermentation. The filtrate obtained were used as sources of the extra-cellular enzymes. The FTase activities and the course of pH in submerged fermentation ranged from 7.53-24.42µ/ml and 4.4-4.8 respectively. The maximum FTase activity was obtained at 48 hours fermentation. In solid state fermentation, FTase activities ranged from 2.41-27.77µ/ml. Using ripe plantain peel and kola nut pod respectively. Both substrates supported the growth of the fungus, producing profuse growth during fermentation. In the control experiment (using kolanut pod) that lack supplementation, appreciable FTase activity of 16.92µ/ml was obtained. The optimum temperature range was 600C. it was also active at broad pH range of 1-9 with optimum obtain at pH of 5.0. FTase was stable within the range of investigated pH showing more than 60% activities. FTase can be used in the production of fructooligosaccharide, a functional food.

Keywords: Aspergillus niger, solid state fermentation, kola nut pods, Fructosyltransferase (FTase)

Procedia PDF Downloads 434

Authors: Itzel Amaro-Estrada, Eduardo Vergara-Rivera, Virginia Juarez-Flores, Mayra Cobaxin-Cardenas, Rosa Estela Quiroz, Jesus F. Preciado, Sergio Rodriguez-Camarillo

Abstract:

Bovine anaplasmosis is an infectious, tick-borne disease caused mainly by Anaplasma marginale; typical signs include anemia, fever, abortion, weight loss, decreased milk production, jaundice, and potentially death. Sick bovine can recover when antibiotics are administered; however, it usually remains as carrier for life, being a risk of infection for susceptible cattle. Anaplasma marginale is an obligate intracellular Gram-negative bacterium with genetic composition highly diverse among geographical isolates. There are currently no vaccines fully effective against bovine anaplasmosis; therefore, the economic losses due to disease are present. Vaccine formulation became a hard task for several pathogens as Anaplasma marginale, but peptide-based vaccines are an interesting proposal way to induce specific responses. Phage-displayed peptide libraries have been proved one of the most powerful technologies for identifying specific ligands. Screening of these peptides libraries is also a tool for studying interactions between proteins or peptides. Thus, it has allowed the identification of ligands recognized by polyclonal antiserums, and it has been successful for the identification of relevant epitopes in chronic diseases and toxicological conditions. Protective immune response to bovine anaplasmosis includes high levels of immunoglobulins subclass G2 (IgG2) but not subclass IgG1. Therefore, IgG2 from the serum of protected bovine can be useful to identify ligands, which can be part of an immunogen for cattle. In this work, phage display random peptide library Ph.D. ™ -12 was incubating with IgG2 or blood sera of immunized bovines against A. marginale as targets. After three rounds of biopanning, several candidates were selected for additional analysis. Subsequently, their reactivity with sera immunized against A. marginale, as well as with positive and negative sera to A. marginale was evaluated by immunoassays. A collection of recognized peptides tested by ELISA was generated. More than three hundred phage-peptides were separately evaluated against molecules which were used during panning. At least ten different peptides sequences were determined from their nucleotide composition. In this approach, three phage-peptides were selected by their binding and affinity properties. In the case of the development of vaccines or diagnostic reagents, it is important to evaluate the immunogenic and antigenic properties of the peptides. Immunogenic in vitro and in vivo behavior of peptides will be assayed as synthetic and as phage-peptide for to determinate their vaccine potential. Acknowledgment: This work was supported by grant SEP-CONACYT 252577 given to I. Amaro-Estrada.

Keywords: bovine anaplasmosis, peptides, phage display, veterinary vaccines

Procedia PDF Downloads 122