Search results for: leaf N content
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6503

Search results for: leaf N content

3293 Study of First Hydrogenation Kinetics at Different Temperatures of BCC Alloy 52Ti-12V-36Cr + x wt% Zr (x = 4, 8 & 12)

Authors: Ravi Prakash

Abstract:

The effects of Zr addition on kinetics and hydrogen absorption characteristics of BCC alloy 52Ti-12V-36Cr doped with x wt% of Zr (x = 0, 4, 8 & 12) was investigated. The samples have been characterized by X-ray diffraction, and activation study were made at four different temperatures- 100 oC, 200 oC, 300 oC and 400 oC. First hydrogenation kinetics of alloys were studied at 20 bar of hydrogen pressure and room temperature after giving heat treatment at different temperatures for 6 hours. Among the various Zr doped alloys studied, the composition 52Ti-12V-36Cr + 4wt% Zr shows maximum hydrogen storage capacity of 3.6wt%. Small amount of Zr shows advantageous effects on kinetics of alloy. It was also found out that alloys with the higher Zr concentration can be activated by giving heat treatment at lower temperatures. There is reduction in hydrogen storage capacity with increasing Zr content in the alloy primarily due to increasing abundance of secondary phase as established by X-Ray Diffraction and Scanning Electron Microscope results.

Keywords: hydrogen storage, metal hydrides, bcc alloy, heat treatment

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3292 Antioxidant Activity of Germinated African Yam Bean (Sphenostylis Stenocarpa) in Alloxan Diabetic Rats

Authors: N. Uchegbu Nneka

Abstract:

This study was conducted to investigate the effect of the antioxidant activity of germinated African Yam Bean (AYB) on oxidative stress markers in alloxan-induced diabetic rat. Rats were randomized into three groups; control, diabetic and germinated AYB–treated diabetic rats. The Total phenol and flavonoid content and DPPH radical scavenging activity before and after germination were investigated. The glucose level, lipid peroxidation and reduced glutathione of the animals were also determined using the standard technique for four weeks. Germination increased the total phenol, flavonoid and antioxidant activity of AYB extract by 19.14%, 32.28%, and 57.25% respectively. The diabetic rats placed on germinated AYB diet had a significant decrease in the blood glucose and lipid peroxidation with a corresponding increase in glutathione (p<0.05). These results demonstrate that consumption of germinated AYB can be a good dietary supplement in inhibiting hyperglycemia/hyperlipidemia and the prevention of diabetic complication associated with oxidative stress.

Keywords: African yam bean, antioxidant, diabetes, total phenol

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3291 Effect of Non-Fat Solid Ratio on Bloom Formation in Untempered Chocolate

Authors: Huanhuan Zhao, Bryony J. James

Abstract:

The relationship between the non-fat solid ratio and bloom formation in untempered chocolate was investigated using two types of chocolate: model chocolate made of varying cocoa powder ratios (46, 49.5 and 53%) and cocoa butter, and commercial Lindt chocolate with varying cocoa content (70, 85 and 90%). X-ray diffraction and colour measurement techniques were used to examine the polymorphism of cocoa butter and the surface whiteness index (WI), respectively. The polymorphic transformation of cocoa butter was highly correlated with the changes of WI during 30 days of storage since it led to the redistribution of fat within the chocolate matrix and resulted in a bloomed surface. The change in WI indicated a similar bloom rate in the chocolates, but the model chocolates with a higher cocoa powder ratio had more pronounced total bloom. This is due to a higher ratio of non-fat solid particles on the surface resulting in microscopic changes in morphology. The ratio of non-fat solids is an important factor in determining the extent of bloom but not the bloom rate.

Keywords: untempered chocolate, microstructure of bloom, polymorphic transformation, surface whiteness

Procedia PDF Downloads 334
3290 Assessment of the Response of Seismic Refraction Tomography and Resistivity Imaging to the Same Geologic Environment: A Case Study of Zaria Basement Complex in North Central Nigeria

Authors: Collins C. Chiemeke, I. B. Osazuwa, S. O. Ibe, G. N. Egwuonwu, C. D. Ani, E. C. Chii

Abstract:

The study area is Zaria, located in the basement complex of northern Nigeria. The rock type forming the major part of the Zaria batholith is granite. This research work was carried out to compare the responses of seismic refraction tomography and resistivity tomography in the same geologic environment and under the same conditions. Hence, the choice of the site that has a visible granitic outcrop that extends across a narrow stream channel and is flanked by unconsolidated overburden, a neutral profile that was covered by plain overburden and a site with thick lateritic cover became necessary. The results of the seismic and resistivity tomography models reveals that seismic velocity and resistivity does not always simultaneously increase with depth, but their responses in any geologic environment are determined by changes in the mechanical and chemical content of the rock types rather than depth.

Keywords: environment, resistivity, response, seismic, velocity

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3289 Applications of Copper Sensitive Fluorescent Dye to the Studies of the Role of Copper in Cisplatin Resistance in Human Cancer

Authors: Sumayah Mohammed Asiri A., Aviva Levina B., Elizabeth New C., Peter Lay D.

Abstract:

Pt compounds have been among the most successful anticancer drugs in the last 40 years, but the development of resistance to them is an increasing problem. Cellular homeostasis of an essential metal, Cu, is known to be involved in Pt resistance, but mechanisms of this process are poorly understood. We used a novel ratiometric Cu(I)-sensitive fluorescent probeInCCu1 dye to detect Cu(I) in the mitochondria. Total Cu and labile Cu pool measured using AAS and InCCu1 dye in A2780 cells and their corresponding resistant cells A2780-cis.R cells treated with Cu and cisplatin. The main difference between both cell lines in the presence and absence of Cu(II) is that resistant cells have lower total Cu content but higher labile Cu levels than cisplatin-sensitive cells. This means that resistant cells can metabolize and export excess Cu more efficiently. Furthermore, InCCu1 has emerged not only as an indicator of labile cellular Cu levels in the mitochondria but as a potentially versatile multi-organelle probe.

Keywords: AAS and ICPMS, A2780 and its resistant cells, ratiometric fluorescent sensors, inCCu1, and total and labile Cu

Procedia PDF Downloads 192
3288 Towards Optimising Building Information Modelling and Building Management System in Higher Education Institutions Facility Management: A Review

Authors: Zhuoqun Sun, Francisco Sierra, A. Booth

Abstract:

With BIM rapidly implemented in the design and construction stage of a project, researchers begin to focus on improving the operation and maintenance stage with the aid of BIM. Since the increasing amount of electronic equipment installed in the building, building management system becomes mainstream for controlling a building, especially in higher education institutions that can play an important role in terms of reducing carbon emission and improving energy efficiency. Currently, an approach to integrate BIM and BMS to improve HEIs facility management has not been established yet. Thus, this paper aims to analyse the benefits, issues, and trends of BIM and BMS integration and their application in HEIs. A systematic literature review was carried out on SCOPUS by applying the PRISMA methodology. 73 articles have been chosen based on keywords, abstracts, and the full content of the articles. The benefit and existed issues from the articles are analysed. The review shows the need to develop a tool to improve facility management through BIM BMS integration.

Keywords: BIM, BMS, HEIs, review

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3287 Enzymatic Determination of Limonene in Red Clover Genotypes

Authors: Andrés Quiroz, Emilio Hormazabal, Ana Mutis, Fernando Ortega, Manuel Chacón-Fuentes, Leonardo Parra

Abstract:

Red clover (Trifolium pratense L.) is an important forage species in temperate regions of the world. The main limitation of this species worldwide is a lack of persistence related to the high mortality of plants due to a complex of biotic and abiotic factors, determining a life span of two or three seasons. Because of the importance of red clover in Chile, a red clover breeding program was started at INIA Carillanca Research Center in 1989, with the main objective of improving the survival of plants, forage yield, and persistence. The main selection criteria for selecting new varieties have been based on agronomical parameters and biotic factors. The main biotic factor associated with red clover mortality in Chile is Hylastinus obscurus (Coleoptera: Curculionidae). Both larval and adults feed on the roots, causing weakening and subsequent death of clover plants. Pesticides have not been successful for controlling infestations of this root borer. Therefore, alternative strategies for controlling this pest are a high priority for red clover producers. Currently, the role of semiochemical in the interaction between H. obscurus and red clover plants has been widely studied for our group. Specifically, from the red clover foliage has been identified limonene is eliciting repellency from the root borer. Limonene is generated in the plant from two independent biosynthetic pathways, the mevalonic acid, and deoxyxylulose pathway. Mevalonate pathway enzymes are localized in the cytosol, whereas the deoxyxylulose phosphate pathway enzymes are found in plastids. In summary, limonene can be determinated by enzymatic bioassay using GPP as substrate and by limonene synthase expression. Therefore, the main objective of this work was to study genetic variation of limonene in material provided by INIA´s Red Clover breeding program. Protein extraction was carried out homogenizing 250 mg of leave tissue and suspended in 6 mL of extraction buffer (PEG 1500, PVP-30, 20 mM MgCl2 and antioxidants) and stirred on ice for 20 min. After centrifugation, aliquots of 2.5 mL were desalted on PD-10 columns, resulting in a final volume of 3.5 mL. Protein determination was performed according to Bradford with BSA as a standard. Monoterpene synthase assays were performed with 50 µL of protein extracts transferred into gas-tight 2 mL crimp seal vials after addition of 4 µL MgCl₂ and 41 µL assay buffer. The assay was started by adding 5 µL of a GPP solution. The mixture was incubated for 30 min at 40 °C. Biosynthesized limonene was quantified in a GC equipped with a chiral column and using synthetic R and S-limonene standards. The enzymatic the production of R and S-limonene from different Superqueli-Carillanca genotypes is shown in this work. Preliminary results showed significant differences in limonene content among the genotypes analyzed. These results constitute an important base for selecting genotypes with a high content of this repellent monoterpene towards H. obscurus.

Keywords: head space, limonene enzymatic determination, red clover, Hylastinus obscurus

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3286 C-Coordinated Chitosan Metal Complexes: Design, Synthesis and Antifungal Properties

Authors: Weixiang Liu, Yukun Qin, Song Liu, Pengcheng Li

Abstract:

Plant diseases can cause the death of crops with great economic losses. Particularly, those diseases are usually caused by pathogenic fungi. Metal fungicides are a type of pesticide that has advantages of a low-cost, broad antimicrobial spectrum and strong sterilization effect. However, the frequent and wide application of traditional metal fungicides has caused serious problems such as environmental pollution, the outbreak of mites and phytotoxicity. Therefore, it is critically necessary to discover new organic metal fungicides alternatives that have a low metal content, low toxicity, and little influence on mites. Chitosan, the second most abundant natural polysaccharide next to cellulose, was proved to have broad-spectrum antifungal activity against a variety of fungi. However, the use of chitosan was limited due to its poor solubility and weaker antifungal activity compared with commercial fungicide. Therefore, in order to improve the water solubility and antifungal activity, many researchers grafted the active groups onto chitosan. The present work was to combine free metal ions with chitosan, to prepare more potent antifungal chitosan derivatives, thus, based on condensation reaction, chitosan derivative bearing amino pyridine group was prepared and subsequently followed by coordination with cupric ions, zinc ions and nickel ions to synthesize chitosan metal complexes. The calculations by density functional theory (DFT) show that the copper ions and nickel ions underwent dsp2 hybridization, the zinc ions underwent sp3 hybridization, and all of them are coordinated by the carbon atom in the p-π conjugate group and the oxygen atoms in the acetate ion. The antifungal properties of chitosan metal complexes against Phytophthora capsici (P. capsici), Gibberella zeae (G. zeae), Fusarium oxysporum (F. oxysporum) and Botrytis cinerea (B. cinerea) were also assayed. In addition, a plant toxicity experiment was carried out. The experiments indicated that the derivatives have significantly enhanced antifungal activity after metal ions complexation compared with the original chitosan. It was shown that 0.20 mg/mL of O-CSPX-Cu can 100% inhibit the growth of P. capsici and 0.20 mg/mL of O-CSPX-Ni can 87.5% inhibit the growth of B. cinerea. In general, their activities are better than the positive control oligosaccharides. The combination of the pyridine formyl groups seems to favor biological activity. Additionally, the ligand fashion was precisely analyzed, and the results revealed that the copper ions and nickel ions underwent dsp2 hybridization, the zinc ions underwent sp3 hybridization, and the carbon atoms of the p-π conjugate group and the oxygen atoms of acetate ion are involved in the coordination of metal ions. The phytotoxicity assay of O-CSPX-M was also conducted, unlike the traditional metal fungicides, the metal complexes were not significantly toxic to the leaves of wheat. O-CSPX-Zn can even increase chlorophyll content in wheat leaves at 0.40 mg/mL. This is mainly because chitosan itself promotes plant growth and counteracts the phytotoxicity of metal ions. The chitosan derivative described here may lend themselves to future applicative studies in crop protection.

Keywords: coordination, chitosan, metal complex, antifungal properties

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3285 Identification of ω-3 Fatty Acids Using GC-MS Analysis in Extruded Spelt Product

Authors: Jelena Filipovic, Marija Bodroza-Solarov, Milenko Kosutic, Nebojsa Novkovic, Vladimir Filipovic, Vesna Vucurovic

Abstract:

Spelt wheat is suitable raw material for extruded products such as pasta, special types of bread and other products of altered nutritional characteristics compared to conventional wheat products. During the process of extrusion, spelt is exposed to high temperature and high pressure, during which raw material is also mechanically treated by shear forces. Spelt wheat is growing without the use of pesticides in harsh ecological conditions and in marginal areas of cultivation. So it can be used for organic and health safe food. Pasta is the most popular foodstuff; its consumption has been observed to rise. Pasta quality depends mainly on the properties of flour raw materials, especially protein content and its quality but starch properties are of a lesser importance. Pasta is characterized by significant amounts of complex carbohydrates, low sodium, total fat fiber, minerals, and essential fatty acids and its nutritional value can be improved with additional functional component. Over the past few decades, wheat pasta has been successfully formulated using different ingredients in pasta to cater health-conscious consumers who prefer having a product rich in protein, healthy lipids and other health benefits. Flaxseed flour is used in the production of bakery and pasta products that have properties of functional foods. However, it should be taken into account that food products retain the technological and sensory quality despite the added flax seed. Flaxseed contains important substances in its composition such as vitamins and minerals elements, and it is also an excellent source of fiber and one of the best sources of ω-3 fatty acids and lignin. In this paper, the quality and identification of spelt extruded product with the addition of flax seed, which is positively contributing to the nutritive and technology changes of the product, is investigated. ω-3 fatty acids are polyunsaturated essential fatty acids, and they must be taken with food to satisfy the recommended daily intake. Flaxseed flour is added in the quantity of 10/100 g of sample and 20/100 g of sample on farina. It is shown that the presence of ω-3 fatty acids in pasta can be clearly distinguished from other fatty acids by gas chromatography with mass spectrometry. Addition of flax seed flour influence chemical content of pasta. The addition of flax seed flour in spelt pasta in the quantities of 20g/100 g significantly increases the share of ω-3 fatty acids, which results in improved ratio of ω-6/ω-3 1:2.4 and completely satisfies minimum daily needs of ω-3 essential fatty acids (3.8 g/100 g) recommended by FDA. Flex flour influenced the pasta quality by increasing of hardness (2377.8 ± 13.3; 2874.5 ± 7.4; 3076.3 ± 5.9) and work of shear (102.6 ± 11.4; 150.8 ± 11.3; 165.0 ± 18.9) and increasing of adhesiveness (11.8 ± 20.6; 9.,98 ± 0.12; 7.1 ± 12.5) of the final product. Presented data point at good indicators of technological quality of spelt pasta with flax seed and that GC-MS analysis can be used in the quality control for flax seed identification. Acknowledgment: The research was financed by the Ministry of Education and Science of the Republic of Serbia (Project No. III 46005).

Keywords: GC-MS analysis, ω-3 fatty acids, flex seed, spelt wheat, daily needs

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3284 Effect of Filler Size and Shape on Positive Temperature Coefficient Effect

Authors: Eric Asare, Jamie Evans, Mark Newton, Emiliano Bilotti

Abstract:

Two types of filler shapes (sphere and flakes) and three different sizes are employed to study the size effect on PTC. The composite is prepared using a mini-extruder with high-density polyethylene (HDPE) as the matrix. A computer modelling is used to fit the experimental results. The percolation threshold decreases with decreasing filler size and this was observed for both the spherical particles as well as the flakes. This was caused by the decrease in interparticle distance with decreasing filler size. The 100 µm particles showed a larger PTC intensity compared to the 5 µm particles for the metal coated glass sphere and flake. The small particles have a large surface area and agglomeration and this makes it difficult for the conductive network to e disturbed. Increasing the filler content decreased the PTC intensity and this is due to an increase in the conductive network within the polymer matrix hence more energy is needed to disrupt the network.

Keywords: positive temperature coefficient (PTC) effect, conductive polymer composite (CPC), electrical conductivity

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3283 Novel Ti/Al-Cr-Fe Metal Matrix Composites Prepared by Spark Plasma Sintering with Excellent Wear Properties

Authors: Ruitao Li, Zhili Dong, Nay Win Khun, Khiam Aik Khor

Abstract:

In this study, microstructure and sintering mechanism as well as wear resistance properties of Ti/Al-Cr-Fe metal matrix composites (MMCs) fabricated by spark plasma sintering (SPS) with Ti as matrix and Al-Cr-Fe as reinforcement were investigated. Phases and microstructure of the sintered samples were analyzed using X-ray diffractometry (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and transmission electron microscopy (TEM). Wear resistance properties were tested by ball-on-disk method. An Al3Ti ring forms around each Al-Cr-Fe particle as the bonding layer between Ti and Al-Cr-Fe particles. The Al content in Al-Cr-Fe particles experiences a decrease from 70 at.% to 60 at.% in the sintering process. And these particles consist of quasicrystalline icosahedral AlCrFe and quasicrystal approximants γ-brass Al8(Cr,Fe)5 and Al9(Cr,Fe)4 in the sintered compact. The addition of Al-Cr-Fe particles into the Ti matrix can improve the microhardness by about 40% and the wear resistance is improved by more than 50% due to the increase in the microhardness and the change of wear mechanism.

Keywords: metal matrix composites, spark plasma sintering, phase transformation, wear

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3282 Valorization of Sawdust for the Treatment of Purified Water for Irrigation

Authors: Dalila Oulhaci, Mohammed Zahaf

Abstract:

The watering technique is essential to maintain a moist perimeter around the roots of the crop. This is the case with topical watering, where the soil around the root system can be kept permanently moist between the two extremes of water content. Moreover, one of the oldest methods used since Roman times throughout North Africa and the Near East was based on the repeated pouring of water into porous earthen vessels buried in the ground. In this context, these two techniques have been combined by replacing the earthen vase with plastic bottles filled with sand which release water through their perforated walls into the surrounding soil. The objective of this work is to first determine the purifying power of the activated sludge treatment plant of Toggourt and then that of the bottled Sawdust filter. For the station, the BOD purification rate was (96.5%), the COD purification rate was (87%) and suspended solids (90%). For the bottle, the BOD removal rate was (35%), and COD removal rate was (12.58%). This work falls within the framework of water saving, sustainable development and environmental protection, and also within the framework of agriculture.

Keywords: wasterwater, sawdust, purification, irrigation, touggourt (Algeria)

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3281 Effect of Dehydration Methods of the Proximate Composition, Mineral Content and Functional Properties of Starch Flour Extracted from Maize

Authors: Olakunle M. Makanjuola, Adebola Ajayi

Abstract:

Effect of the dehydrated method on proximate, functional and mineral properties of corn starch was evaluated. The study was carried and to determine the proximate, functional and mineral properties of corn starch produced using three different drying methods namely (sun) (oven) and (cabinet) drying methods. The corn starch was obtained by cleaning, steeping, milling, sieving, dewatering and drying corn starch was evaluated for proximate composition, functional properties, and mineral properties to determine the nutritional properties, moisture, crude protein, crude fat, ash, and carbohydrate were in the range of 9.35 to 12.16, 6.5 to 10.78 1.08 to 2.5, 1.08 to 2.5, 4.0 to 5.2, 69.58 to 75.8% respectively. Bulk density range between 0.610g/dm3 to 0.718 g/dm3, water, and oil absorption capacities range between 116.5 to 117.25 and 113.8 to 117.25 ml/g respectively. Swelling powder had value varying from 1.401 to 1.544g/g respectively. The results indicate that the cabinet method had the best result item of the quality attribute.

Keywords: starch flour, maize, dehydration, cabinet dryer

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3280 Importance of Punctuation in Communicative Competence

Authors: Khayriniso Bakhtiyarovna Ganiyeva

Abstract:

The article explores the significance of punctuation in achieving communicative competence. It underscores that effective communication goes beyond simply using punctuation correctly. In the successful completion of a communicative activity, it is important not that the writer correctly uses punctuation marks but that he was able to achieve a goal aimed at expressing a certain meaning. The unanimity of the writer and the reader in the mutual understanding of the text is of primary importance. It should also be taken into account that situational communication provides special informative content and expressiveness of speech. Also, the norms of the situation are determined by the nature of the information in the text, and the punctuation marks expressed in accordance with the norm perform logical-semantic, highlighting expressive-emotional and signaling functions. It is a mistake to classify the signs subject to the norm of the situation as created by the author because they functionally reflect the general stylistic features of different texts. Such signs are among the common signs that are codified only by the semantics and structure of the created text.

Keywords: communicative-pragmatic approach, expressiveness of speech, stylistic features, comparative analysis

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3279 Research and Application of the Three-Dimensional Visualization Geological Modeling of Mine

Authors: Bin Wang, Yong Xu, Honggang Qu, Rongmei Liu, Zhenji Gao

Abstract:

Today's mining industry is advancing gradually toward digital and visual direction. The three dimensional visualization geological modeling of mine is the digital characterization of mineral deposit, and is one of the key technology of digital mine. The three-dimensional geological modeling is a technology that combines the geological spatial information management, geological interpretation, geological spatial analysis and prediction, geostatistical analysis, entity content analysis and graphic visualization in three-dimensional environment with computer technology, and is used in geological analysis. In this paper, the three-dimensional geological modeling of an iron mine through the use of Surpac is constructed, and the weight difference of the estimation methods between distance power inverse ratio method and ordinary kriging is studied, and the ore body volume and reserves are simulated and calculated by using these two methods. Compared with the actual mine reserves, its result is relatively accurate, so it provided scientific bases for mine resource assessment, reserve calculation, mining design and so on.

Keywords: three-dimensional geological modeling, geological database, geostatistics, block model

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3278 Effect of Dual-Oligo Saccharide on Loperamide-Induced Constipation in Rat Model

Authors: So Hyun Ahn, Geu Rim Seo, Byungsoo Shin, Kwang-Won Yu, Hyung Joo Suh, Sung Hee Han

Abstract:

We investigated the effects of GOS, lactulose and DuOligo in loperamide-induced constipation rat model. Dual-Oligo saccharide (DuOligo) was composed with galacto-oligosaccharide (GOS) and lactulose. GOS is an important dietary prebiotics that affects intestinal microbiota and barrier functions to have beneficial effect and lactulose is used as a laxative to treat constipation. To study the DuOligo, after adaptation period of four weeks of Spraque-Dawley rats, loperamide (5 mg/kg, twice per day) was injected to induce constipation for 1 week. DuOligo increased the fecal pellet amount, fecal weight, and water content of feces in rats with loperamide-induced constipation. DuOligo groups tended to produce more total fatty acid than that of observed for the control group. Gastrointestinal transit ratio and length and area of intestinal mucosa increased after treatment with DuOligo in loperamide-induced rats. These results showed that oral administration of DuOligo significantly modulated intestinal peristalsis.

Keywords: constipation, DuOligo, GOS, lactulose

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3277 Spin-Dipole Excitations Produced On-Demand in the Fermi Sea

Authors: Mykhailo Moskalets, Pablo Burset, Benjamin Roussel, Christian Flindt

Abstract:

The single-particle injection from the Andreev level and how such injection is simulated using a voltage pulse are discussed. Recently, high-speed quantum-coherent electron sources injecting one- to few-particle excitations into the Fermi sea have been experimentally realized. The main obstacle to using these excitations as flying qubits for quantum-information processing purposes is decoherence due to the long-range Coulomb interaction. An obvious way to get around this difficulty is to employ electrically neutral excitations. Here it is discussed how such excitations can be generated on-demand using the same injection principles as in existing electron sources. Namely, with the help of a voltage pulse of a certain shape applied to the Fermi sea or using a driven quantum dot with superconducting correlations. The advantage of the latter approach is the possibility of varying the electron-hole content in the excitation and the possibility of creating a charge-neutral but spin-dipole excitation.

Keywords: Andreev level, on-demand, single-electron, spin-dipole

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3276 A Study of the Growth of Single-Phase Mg0.5Zn0.5O Films for UV LED

Authors: Hong Seung Kim, Chang Hoi Kim, Lili Yue

Abstract:

Single-phase, high band gap energy Zn0.5Mg0.5O films were grown under oxygen pressure, using pulse laser deposition with a Zn0.5Mg0.5O target. Structural characterization studies revealed that the crystal structures of the ZnX-1MgXO films could be controlled via changes in the oxygen pressure. TEM analysis showed that the thickness of the deposited Zn1-xMgxO thin films was 50–75 nm. As the oxygen pressure increased, we found that one axis of the crystals did not show a very significant increase in the crystallization compared with that observed at low oxygen pressure. The X-ray diffraction peak intensity for the hexagonal-ZnMgO (002) plane increased relative to that for the cubic-ZnMgO (111) plane. The corresponding c-axis of the h-ZnMgO lattice constant increased from 5.141 to 5.148 Å, and the a-axis of the c-ZnMgO lattice constant decreased from 4.255 to 4.250 Å. EDX analysis showed that the Mg content in the mixed-phase ZnMgO films decreased significantly, from 54.25 to 46.96 at.%. As the oxygen pressure was increased from 100 to 150 mTorr, the absorption edge red-shifted from 3.96 to 3.81 eV; however, a film grown at the highest oxygen pressure tested here (200 mTorr).

Keywords: MgO, UV LED, ZnMgO, ZnO

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3275 Strong Down-Conversion Emission of Sm3+ Doped Borotellurite Glass under the 480nm Excitation Wavelength

Authors: M. R. S. Nasuha, K. Azman, H. Azhan, S. A. Senawi, A. Mardhiah

Abstract:

Studies on Samarium doped glasses possess lot of interest due to their potential applications for high-density optical memory, optical communication device, the design of laser and color display etc. Sm3+ doped borotellurite glasses of the system (70-x) TeO2-20B2O3-10ZnO-xSm2O3 (where x = 0.0, 0.5, 1.0, 1.5, 2.0 and 2.5 mol%) have been prepared using melt-quenching method. Their physical properties such as density, molar volume and oxygen packing density as well as the optical measurements by mean of their absorption and emission characteristic have been carried out at room temperature using UV/VIS and photoluminescence spectrophotometer. The results of physical properties are found to vary with respect to Sm3+ ions content. Meanwhile, three strong absorption peaks are observed and are well resolved in the ultra violet and visible regions due to transitions between the ground state and various excited state of Sm3+ ions. Thus, the photoluminescence spectra exhibit four emission bands from the initial state, which correspond to the 4G5/2 → 6H5/2, 4G5/2 → 6H7/2, 4G5/2 → 6H9/2 and 4G5/2 → 6H11/2 fluorescence transitions at 562 nm, 599 nm, 645 nm and 706 nm respectively.

Keywords: absorption, borotellurite, down-conversion, emission

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3274 Predicting Durability of Self Compacting Concrete Using Artificial Neural Network

Authors: R. Boudjelthia

Abstract:

The aim of this study is to determine the influence of mix composition of concrete as the content of water and cement, water–binder ratio, and the replacement of fly ash on the durability of self compacting concrete (SCC) by using artificial neural networks (ANNs). To achieve this, an ANNs model is developed to predict the durability of self compacting concrete which is expressed in terms of chloride ions permeability in accordance with ASTM C1202-97 or AASHTO T277. Database gathered from the literature for the training and testing the model. A sensitivity analysis was also conducted using the trained and tested ANN model to investigate the effect of fly ash on the durability of SCC. The results indicate that the developed model is reliable and accurate. the durability of SCC expressed in terms of total charge passed over a 6-h period can be significantly improved by using at least 25% fly ash as replacement of cement. This study show that artificial neural network have strong potentialas a feasible tool for predicting accurately the durability of SCC containing fly ash.

Keywords: artificial neural networks, durability, chloride ions permeability, self compacting concrete

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3273 On-line Control of the Natural and Anthropogenic Safety in Krasnoyarsk Region

Authors: T. Penkova, A. Korobko, V. Nicheporchuk, L. Nozhenkova, A. Metus

Abstract:

This paper presents an approach of on-line control of the state of technosphere and environment objects based on the integration of Data Warehouse, OLAP and Expert systems technologies. It looks at the structure and content of data warehouse that provides consolidation and storage of monitoring data. There is a description of OLAP-models that provide a multidimensional analysis of monitoring data and dynamic analysis of principal parameters of controlled objects. The authors suggest some criteria of emergency risk assessment using expert knowledge about danger levels. It is demonstrated now some of the proposed solutions could be adopted in territorial decision making support systems. Operational control allows authorities to detect threat, prevent natural and anthropogenic emergencies and ensure a comprehensive safety of territory.

Keywords: decision making support systems, emergency risk assessment, natural and anthropogenic safety, on-line control, territory

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3272 Creative Means to Address Mental Health in the African American Community: Arts, Advocacy, and Awareness

Authors: Denise F. Brown

Abstract:

This proposal provides an explanation of the content for a Special Topics Course to be offered Spring of 2022. The course will be titled, Creative means to address mental health in the African American Community: Arts, Advocacy, and Awareness. Research shows that African Americans are less likely to seek treatment for mental illnesses. The stigma around mental illness influences negative ideas about having psychological problems within the African American community. Assessments of how African Americans perceive mental illness will also be provided. Current research suggests that understanding mental health is just as important as understanding mental illness. The distinguishment between mental illness and mental health provides a way to not negatively point out mental illness but to better understand that psychological and emotional well-being can be achieved whether a mental illness is present or not. The course will consist of defining mental health and mental illness and then what it means to utilize creative means to become a mental health advocate within the African American community.

Keywords: arts, advocacy, black mental health, mental illness

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3271 Actor Training in Social Work Education: A Pilot Study of Theatre Workshops to Enhance Clinical Empathy

Authors: Amanda Coleman, Estefanía Gonzalez

Abstract:

Empathy is considered an essential skill for engaging with social work clients. Drawing from developments in medical education, researchers will conduct and evaluate a three-part pilot theatre workshop with master level social work students (n ≈ 30) to evaluate the workshop's ability to enhance empathy among participants. Outcomes will be measured using semi-structured post-intervention interviews with a subset of participants (n ≈ 10) as well post-intervention written reflections and pre-and-post intervention quantitative evaluation of empathy using King and Holosko’s 2011 Empathy Scale for Social Workers. The content of the workshop will differ from traditional role plays, which are common in social work education, in that it will draw from role theory and research on creative empathy to emphasize role reversal with clients. Workshops will be held February and March of 2017 with preliminary findings available by April.

Keywords: education, empathy, social work, theatre

Procedia PDF Downloads 252
3270 A Comparative Analysis of Hyper-Parameters Using Neural Networks for E-Mail Spam Detection

Authors: Syed Mahbubuz Zaman, A. B. M. Abrar Haque, Mehedi Hassan Nayeem, Misbah Uddin Sagor

Abstract:

Everyday e-mails are being used by millions of people as an effective form of communication over the Internet. Although e-mails allow high-speed communication, there is a constant threat known as spam. Spam e-mail is often called junk e-mails which are unsolicited and sent in bulk. These unsolicited emails cause security concerns among internet users because they are being exposed to inappropriate content. There is no guaranteed way to stop spammers who use static filters as they are bypassed very easily. In this paper, a smart system is proposed that will be using neural networks to approach spam in a different way, and meanwhile, this will also detect the most relevant features that will help to design the spam filter. Also, a comparison of different parameters for different neural network models has been shown to determine which model works best within suitable parameters.

Keywords: long short-term memory, bidirectional long short-term memory, gated recurrent unit, natural language processing, natural language processing

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3269 Evaluation of Herbal Extracts for Their Potential Application as Skin Prebiotics

Authors: Anja I. Petrov, Milica B. Veljković, Marija M. Ćorović, Ana D. Milivojević, Milica B. Simović, Katarina M. Banjanac, Dejan I. Bezbradica

Abstract:

One of the fundamental requirements for overall human well-being is a stable and balanced microbiome. Aside from the microorganisms that reside within the body, a large number of microorganisms, especially bacteria, swarming the human skin is in homeostasis with the host and represents a skin microbiota. Even though the immune system of the skin is capable of distinguishing between commensal and potentially harmful transient bacteria, the cutaneous microbial balance can be disrupted under certain circumstances. In that case, a reduction in the skin microbiota diversity, as well as changes in metabolic activity, results in dermal infections and inflammation. Probiotics and prebiotics have the potential to play a significant role in the treatment of these skin disorders. The most common resident bacteria found on the skin, Staphylococcus epidermidis, can act as a potential skin probiotic, contributing to the protection of healthy skin from pathogen colonization, such as Staphylococcus aureus, which is related to atopic dermatitis exacerbation. However, as it is difficult to meet regulations in cosmetic products, another therapy approach could be topical prebiotic supplementation of the skin microbiota. In recent research, polyphenols are attracting scientists' interest as biomolecules with possible prebiotic effects on the skin microbiota. This research aimed to determine how herbal extracts rich in different polyphenolic compounds (lemon balm, St. John's wort, coltsfoot, pine needle, and yarrow) affected the growth of S. epidermidis and S. aureus. The first part of the study involved screening plants to determine if they could be regarded as probable candidates to be skin prebiotics. The effect of each plant on bacterial growth was examined by supplementing the nutrient medium with their extracts and comparing it with control samples (without extract). The results obtained after 24 h of incubation showed that all tested extracts influenced the growth of the examined bacteria to some extent. Since lemon balm and St. John's wort extracts displayed bactericidal activity against S. epidermidis, whereas coltsfoot inhibited both bacteria equally, they were not explored further. On the other hand, pine needles and yarrow extract led to an increase in S. epidermidis/S. aureus ratio, making them prospective candidates to be used as skin prebiotics. By examining the prebiotic effect of two extracts at different concentrations, it was revealed that, in the case of yarrow, 0.1% of extract dry matter in the fermentation medium was optimal, while for the pine needle extract, a concentration of 0.05% was preferred, since it selectively stimulated S. epidermidis growth and inhibited S. aureus proliferation. Additionally, the total polyphenols and flavonoid content of the two extracts were determined, revealing different concentrations and polyphenol profiles. Since yarrow and pine extracts affected the growth of skin bacteria in a dose-dependent manner, by carefully selecting the quantities of these extracts, and thus polyphenols content, it is possible to achieve desirable alterations of skin microbiota composition, which may be suitable for the treatment of atopic dermatitis.

Keywords: herbal extracts, polyphenols, skin microbiota, skin prebiotics

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3268 Biocompatible Hydrogel Materials Containing Cytostatics for Cancer Treatment

Authors: S. Kudlacik-Kramarczyk, M. Kedzierska, B. Tyliszczak

Abstract:

Recently, the continuous development of medicine and related sciences has been observed. Particular emphasis is directed on the development of biomaterials, i.e., non-toxic, biocompatible and biodegradable materials that may improve the effectiveness of treatment as well as the comfort of patients. This is particularly important in the case of cancer treatment. Currently, there are many methods of cancer treatment based primarily on chemotherapy and the surgical removal of the tumor, but it is worth noting that these therapies also cause many side effects. Among women, the most common cancer is breast cancer. It may be completely cured, but the consequence of treatment is partial or complete breast mastectomy and radiation therapy, which results in severe skin burns. The skin of the patient after radiation therapy is very burned, and therefore requires intensive care and high frequency of dressing changes. The traditional dressing adheres to the burn wounds and does not absorb adequate amount of exudate from injuries and the patient is forced to change the dressing every 2 hours. Therefore, the main purpose was to develop an innovative combination of dressing material with drug carriers that may be used in anti-cancer therapy. The innovation of this solution is the combination of these two products into one system, i.e., a transdermal system with the possibility of a controlled release of the drug- cytostatic. Besides, the possibility of modifying the hydrogel matrix with aloe vera juice provides this material with new features favorable from the point of view of healing processes of burn wounds resulting from the radiation therapy. In this study, hydrogel materials containing protein spheres with the active substance have been obtained as a result of photopolymerization process. The reaction mixture consisting of the protein (albumin) spheres incorporated with cytostatic, chitosan, adequate crosslinking agent and photoinitiator has been subjected to the UV radiation for 2 minutes. Prepared materials have been subjected to the numerous studies including the analysis of cytotoxicity using murine fibroblasts L929. Analysis was conducted based on the mitochondrial activity test (MTT reduction assay) which involves the determining the number of cells characterized by proper metabolism. Hydrogel materials obtained using different amount of crosslinking agents have been subjected to the cytotoxicity analysis. According to the standards, tested material is defined as cytotoxic when the viability of cells after 24 h incubation with this material is lower than 70%. In the research, hydrogel polymer materials containing protein spheres incorporated with the active substance, i.e. a cytostatic, have been developed. Such a dressing may support the treatment of cancer due to the content of the anti-cancer drug - cytostatic, and may also provide a soothing effect on the healing of the burn wounds resulted from the radiation therapy due to the content of aloe vera juice in the hydrogel matrix. Based on the conducted cytotoxicity studies, it may be concluded that the obtained materials do not adversely affect the tested cell lines, therefore they can be subjected to more advanced analyzes.

Keywords: hydrogel polymers, cytostatics, drug carriers, cytotoxicity

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3267 Information and Communication Technology and Business Education in Nigeria

Authors: Oloniyo Kemisola Eunice, Odere Oladunni Oluwafeyikemi

Abstract:

Technological change and globalization have created a new global economy with Information and Communication Technology (ICT) occupying a complex position in relation to globalization. The emergence of this new global economy has serious implications on the nature and purpose of educational institutions. The paper is basically a theoretical discourse. Data for analysis were obtained from secondary sources. The paper found that significant challenges confront the integration of ICTs in education in the areas of educational policy and planning, infrastructure, language and content, capacity building and financing in Nigeria. The paper concluded that business education needs to be well equipped to anticipate and respond to opportunities created by ICTs in order to participate productively and equitably in an increasingly technology-rich and knowledge-driven world. The paper recommended, among others, that the investments in ICTs should be used to promote the development of basic skills, problem-solving and communication skills and the professional development of teachers.

Keywords: information, communication, technology, business, education

Procedia PDF Downloads 363
3266 Impact of Machining Parameters on the Surface Roughness of Machined PU Block

Authors: Louis Denis Kevin Catherine, Raja Aziz Raja Ma’arof, Azrina Arshad, Sangeeth Suresh

Abstract:

Machining parameters are very important in determining the surface quality of any material. In the past decade, some new engineering materials were developed for the manufacturing industry which created a need to conduct an investigation on the impact of the said parameters on their surface roughness. The polyurethane (PU) block is widely used in the automotive industry to manufacture parts such as checking fixtures that are used to verify the dimensional accuracy of automotive parts. In this paper, the design of experiment (DOE) was used to investigate the effect of the milling parameters on the PU block. Furthermore, an analysis of the machined surface chemical composition was done using scanning electron microscope (SEM). It was found that the surface roughness of the PU block is severely affected when PU undergoes a flood machining process instead of a dry condition. In addition, the step over and the silicon content were found to be the most significant parameters that influence the surface quality of the PU block.

Keywords: polyurethane (PU), design of experiment (DOE), scanning electron microscope (SEM), surface roughness

Procedia PDF Downloads 504
3265 Social Affiliation Effects of Technology in 2022

Authors: Johanna Goeß

Abstract:

In this field study, it is hypothesised that affiliation motivation is relevant to dark terminal technology readiness. The theoretical basis for this work was the TAM 2, focusing on the social process variables and the short-scale technology readiness. Two hypotheses to be tested are the focus of consideration:
 H1: The TAM constructs are independently positively related to dark device use. H2: Sense of social belonging is positively related to dark device use.
 In this quantitative study, 30 male subjects participated with their dark devices. Using a post-basket exercise, affiliation is manipulated by content items on the website to investigate whether affiliation between computers and people and smartphones and people leads to similar effects as an affiliation between people. The entire scientific study, including the questionnaire, took about 30 minutes. This study contributes to the current literature and draws attention to the fact that male users' terminal devices have an influence in the form of affiliation effects.

Keywords: human-computer-interaction, computers, smartphones, addiction, social affiliation effects, TAM 2, pyramid of needs, social actors

Procedia PDF Downloads 103
3264 Study on Preparation and Storage of Jam Incorporating Carrots (Dacus Carrota), Banana (Musa Acuminata) and Lime (Citrus Aurantifola)

Authors: K. Premakumar, D. S. Rushani, H. N. Hettiarachchi

Abstract:

The production and consumption of preserved foods have gained much importance due to globalization, and they provide a health benefit apart from the basic nutritional functions. Therefore, a study was conducted to develop a jam incorporating carrot, banana, and lime. Considering the findings of several preliminary studies, five formulations of the jam were prepared by blending different percentages of carrot and banana including control (where the only carrot was added). The freshly prepared formulations were subjected to physicochemical and sensory analysis.Physico-Chemical parameters such as pH, TSS, titrable acidity, ascorbic acid content, total sugar and non-reducing sugar and organoleptic qualities such as colour, aroma, taste, spread ability and overall acceptability and microbial analysis (total plate count) were analyzed after formulations. Physico-Chemical Analysis of the freshly prepared Carrot –Banana Blend jam showed increasing trend in titrable acidity (from 0.8 to 0.96, as % of citric acid), TSS (from 70.05 to 67.5 0Brix), ascorbic acid content (from 0.83 to 11.465 mg/100ml), reducing sugar (from 15.64 to 20.553%) with increase in carrot pulp from 50 to 100%. pH, total sugar, and non-reducing sugar were also reduced when carrot concentration is increased. Five points hedonic scale was used to evaluate the organoleptic characters. According to Duncan's Multiple Range Test, the mean scores for all the assessed sensory characters varied significantly (p<0.05) in the freshly made carrot-banana blend jam formulations. Based on the physicochemical and sensory analysis, the most preferred carrot: banana combinations of 50:50, 100:0 and 80:20 (T1, T2, and T5) were selected for storage studies.The formulations were stored at 300 °C room temperature and 70-75% of RH for 12 weeks. The physicochemical characteristics were measured at two weeks interval during storage. The decreasing trends in pH and ascorbic acid and an increasing trend in TSS, titrable acidity, total sugar, reducing sugar and non-reducing sugar were noted with advancement of storage periods of 12 weeks. The results of the chemical analysis showed that there were significance differences (p<0.05) between the tested formulations. Sensory evaluation was done for carrot –banana blends jam after a period of 12 weeks through a panel of 16 semi-trained panelists. The sensory analysis showed that there were significant differences (p<0.05) for organoleptic characters between carrot-banana blend jam formulations. The highest overall acceptability was observed in formulation with 80% carrot and 20% banana pulp. Microbiological Analysis was carried out on the day of preparation, 1 month, 2 months and 3 months after preparation. No bacterial growth was observed in the freshly made carrot -banana blend jam. There were no counts of yeast and moulds and coliforms in all treatments after the heat treatments and during the storage period. Only the bacterial counts (Total Plate Counts) were observed after three months of storage below the critical level, and all formulations were microbiologically safe for consumption. Based on the results of physio-chemical characteristics, sensory attributes, and microbial test, the carrot –banana blend jam with 80% carrot and 20% banana (T2) was selected as best formulation and could be stored up to 12 weeks without any significant changes in the quality characteristics.

Keywords: formulations, physicochemical parameters, microbiological analysis, sensory evaluation

Procedia PDF Downloads 194