Search results for: functional property
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4313

Search results for: functional property

3443 Functional Diversity of Pseudomonas: Role in Stimulation of Bean Germination and Common Blight Biocontrol

Authors: Slimane Mokrani, Nabti El hafid

Abstract:

Description of the subject: Currently, several efforts focus on the study of biodiversity, microbial biotechnology, and the use of ecological strategies. Objectives: The aim of this present work is to determine the functional diversity of bacteria in rhizospheric and non-rhizospheric soils of different plants. Methods: Bacteria were isolated from soil and identified based on physiological and biochemical characters and genotypic taxonomy performed by 16S rDNA and BOX-PCR. As well as the characterization of various PGPR traits. Then, they are tested for their effects on the stimulation of seed germination and the growth of Phaseolus vulgaris L. As well as their biological control activities with regard to the phytopathogenic bacterial isolate Xapf. Results and Discussion: The biochemical and physiological identification of 75 bacterial isolates made it possible to associate them with the two groups of fluorescent Pseudomonas (74.67%) and non-fluorescent Pseudomonas (25.33%). The identification by 16S rDNA of 27 strains made it possible to attribute the majority of the strains to the genus Pseudomonas (81.48%), Serratia (7.41%) and Bacillus (11.11%). The bacterial strains showed a high capacity to produce IAA, siderophores, HCN and to solubilize phosphate. A significant stimulation of germination and growth was observed by applying the Pseudomonas strains. Furthermore, significant reductions in the severity and intensity of the disease caused caused by Xapf were observed. Conclusion: The bacteria described in this present study endowed with different PGPR activities seem to be very promising for their uses as biological control agents and bio-fertilization.

Keywords: biofertilization, biological control, phaseolus vulgaris L, pseudomonas, Xanthomonas axonopodis pv. phaseoli var. fuscans and common blight

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3442 The Functional Rehabilitation of Peri-Implant Tissue Defects: A Case Report

Authors: Özgür Öztürk, Cumhur Sipahi, Hande Yeşil

Abstract:

Implant retained restorations commonly consist of a metal-framework veneered with ceramic or composite facings. The increasing and expanding use of indirect resin composites in dentistry is a result of innovations in materials and processing techniques. Of special interest to the implant restorative field is the possibility that composites present significantly lower peak vertical and transverse forces transmitted at the peri-implant level compared to metal-ceramic supra structures in implant-supported restorations. A 43-year-old male patient referred to the department of prosthodontics for an implant retained fixed prosthesis. The clinical and radiographic examination of the patient demonstrated the presence of an implant in the right mandibular first molar tooth region. A considerable amount of marginal bone loss around the implant was detected in radiographic examinations combined with a remarkable peri-implant soft tissue deficiency. To minimize the chewing loads transmitted to the implant-bone interface it was decided to fabricate an indirect composite resin veneered single metal crown over a screw-retained abutment. At the end of the treatment, the functional and aesthetic deficiencies were fully compensated. After a 6 months clinical and radiographic follow-up period the not any additional pathologic invasion was detected in the implant-bone interface and implant retained restoration did not reveal any vehement complication.

Keywords: dental implant, fixed partial dentures, indirect composite resin, peri-implant defects

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3441 The Effect of Sea Buckthorn (Hippophae rhamnoides L.) Berries on Some Quality Characteristics of Cooked Pork Sausages

Authors: Anna M. Salejda, Urszula Tril, Grażyna Krasnowska

Abstract:

The aim of this study was to analyze selected quality characteristics of cooked pork sausages manufactured with the addition of Sea buckthorn (Hippophae rhamnoides L.) berries preparations. Stuffings of model sausages consisted of pork, backfat, water and additives such a curing salt and sodium isoascorbate. Functional additives used in production process were two preparations obtained from dried Sea buckthorn berries in form of powder and brew. Powder of dried berries was added in amount of 1 and 3 g, while water infusion as a replacement of 50 and 100% ice water included in meat products formula. Control samples were produced without functional additives. Experimental stuffings were heat treated in water bath and stored for 4 weeks under cooled conditions (4±1ºC). Physical parameters of colour, texture profile and technological parameters as acidity, weight losses and water activity were estimated. The effect of Sea buckthorn berries preparations on lipid oxidation during storage of final products was determine by TBARS method. Studies have shown that addition of Sea buckthorn preparations to meat-fatty batters significant (P≤0.05) reduced the pH values of sausages samples after thermal treatment. Moreover, the addition of berries powder caused significant differences (P ≤ 0.05) in weight losses after cooking process. Analysis of results of texture profile analysis indicated, that utilization of infusion prepared from Sea buckthorn dried berries caused increase of springiness, gumminess and chewiness of final meat products. At the same time, the highest amount of Sea buckthorn berries powder in recipe caused the decrease of all measured texture parameters. Utilization of experimental preparations significantly decreased (P≤0.05) lightness (L* parameter of color) of meat products. Simultaneously, introduction of 1 and 3 grams of Sea buckthorn berries powder to meat-fatty batter increased redness (a* parameter) of samples under investigation. Higher content of substances reacting with thiobarbituric acid was observed in meat products produced without functional additives. It was observed that powder of Sea buckthorn berries added to meat-fatty batters caused higher protection against lipid oxidation in cooked sausages.

Keywords: sea buckthorn, meat products, texture, color parameters, lipid oxidation

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3440 Socio-Psychological Significance of Vandalism in the Urban Environment: Destruction, Modernization, Communication

Authors: Olga Kruzhkova, Irina Vorobyeva, Roman Porozov

Abstract:

Vandalism is a common phenomenon, but its definition is still not clearly defined. In the public sense, vandalism is the blatant cases of pogroms in cemeteries, destruction of public places (regardless of whether these actions are authorized), damage to significant objects of culture and history (monuments, religious buildings). From a legal point of view, only such an act can be called vandalism, which is aimed at 'desecrating buildings or other structures, damaging property on public transport or in other public places'. The key here is the notion of public property that is being damaged. In addition, the principal is the semantics of messages, expressed in a kind of sign system (drawing, inscription, symbol), which initially threatens public order, the calmness of citizens, public morality. Because of this, the legal qualification of vandalism doesn’t include a sufficiently wide layer of environmental destructions that are common in modern urban space (graffiti and other damage to private property, broken shop windows, damage to entrances and elevator cabins), which in ordinary consciousness are seen as obvious facts of vandalism. At the same time, the understanding of vandalism from the position of psychology implies an appeal to the question of the limits of the activity of the subject of vandalism and his motivational basis. Also recently, the discourse on the positive meaning of some forms of vandalism (graffiti, street-art, etc.) has been activated. But there is no discussion of the role and significance of vandalism in public and individual life, although, like any socio-cultural and socio-psychological phenomenon, vandalism is not groundless and meaningless. Our aim of the study was to identify and describe the functions of vandalism as a socio-cultural and socio-psychological phenomenon of the life of the urban community, as well as personal determinants of its manifestations. The study was conducted in the spatial environment of the Russian megalopolis (Ekaterinburg) by photographing visual results of vandal acts (6217 photos) with subsequent trace-assessment and image content analysis, as well as diagnostics of personal characteristics and motivational basis of vandal activity of possible subjects of vandalism among youth. The results of the study allowed to identify the functions of vandalism at the socio-environmental and individual-subjective levels. The socio-environmental functions of vandalism include the signaling function, the function of preparing of social changes, the constructing function, and the function of managing public moods. The demonstrative-protest function, the response function, the refund function, and the self-expression function are assigned to the individual-subjective functions of vandalism. A two-dimensional model of vandal functions has been formed, where functions are distributed in the spaces 'construction reconstruction', 'emotional regulation/moral regulation'. It is noted that any function of vandal activity at the individual level becomes a kind of marker of 'points of tension' at the social and environmental level. Acknowledgment: The research was supported financially by Russian Science Foundation, (Project No. 17-18-01278).

Keywords: destruction, urban environment, vandal behavior, vandalism, vandalism functions

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3439 Production and Quality Assessment of Antioxidant-Rich Biscuit Produced from Pearl Millet and Orange Peel Flour Blends

Authors: Oloniyo Rebecca Olajumoke

Abstract:

The unstable free radicals molecules oxidize cells throughout the body to cause oxidative stress, which has been implicated in the pathogenesis of many chronic diseases. Thus, the consumption of antioxidant-rich snacks could help to reduce the production of these free radicals in the body. This study aimed at producing antioxidant–rich biscuits from an underutilized pearl millet and agricultural waste from orange peel flour (PMF and OPF, respectively) blends. Biscuits were produced from PMF, and OPF blends using various proportions (95:05; 90:10; 85:15; 80:20 with 100% PMF as control. The functional properties of the flours, as well as the antioxidant properties, physical evaluation, and consumer acceptability of the biscuits, were evaluated. The functional properties of the composite flour showed an increase in oil absorption capacity (7.73-8.80 g/ml), water absorption capacity (6.82-7.21 g/ml), foaming (3.91-5.88 g/ml), and emulsification (52.85-58.82 g/ml) properties. The increased addition of OPF significantly (p<0.05) increased the antioxidant properties of the biscuits produced from the composite flour. For instance, the ferric reducing properties (0.10-0.4 mgAAE/g), total flavonoid (1.20-8.12 mg QE/g), and ABTS radical scavenging (1.17-2.19 mmol/TEAC/g) of the composite flours were increasingly comparable to those of 100% PMF. The physical parameters of the biscuit were significantly different (p<0.05) from one another. The addition of OPF into PMF reduced the weight, diameter, and spread ratio of biscuits produced while contrarily increasing the height of the biscuit. The incorporation of OPF at 5% (95:05) substitution yielded a consumedly acceptable biscuit product. The significant increase in antioxidant properties with an increase in OPF during the production of biscuits would therefore increase the nutritional value and potential health benefits.

Keywords: orange peel, biscuit, antioxidant, pearl millet

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3438 Analysis of the Evolution of Techniques and Review in Cleft Surgery

Authors: Tomaz Oliveira, Rui Medeiros, André Lacerda

Abstract:

Introduction: Cleft lip and/or palate are the most frequent forms of congenital craniofacial anomalies, affecting mainly the middle third of the face and manifesting by functional and aesthetic changes. Bilateral cleft lip represents a reconstructive surgical challenge, not only for the labial component but also for the associated nasal deformation. Recently, the paradigm of the approach to this pathology has changed, placing the focus on muscle reconstruction and anatomical repositioning of the nasal cartilages in order to obtain the best aesthetic and functional results. The aim of this study is to carry out a systematic review of the surgical approach to bilateral cleft lip, retrospectively analyzing the case series of Plastic Surgery Service at Hospital Santa Maria (Lisbon, Portugal) regarding this pathology, the global assessment of the characteristics of the operated patients and the study of the different surgical approaches and their complications in the last 20 years. Methods: The present work demonstrates a retrospective and descriptive study of patients who underwent at least one reconstructive surgery for cleft lip and/or palate, in the CPRE service of the HSM, in the period between January 1 of 1997 and December 31 of 2017, in which the data relating to 361 individuals were analyzed who, after applying the exclusion criteria, constituted a sample of 212 participants. The variables analyzed were the year of the first surgery, gender, age, type of orofacial cleft, surgical approach, and its complications. Results: There was a higher overall prevalence in males, with cleft lip and cleft palate occurring in greater proportion in males, with the cleft palate being more common in females. The most frequently recorded malformation was cleft lip and palate, which is complete in most cases. Regarding laterality, alterations with a unilateral labial component were the most commonly observed, with the left lip being described as the most affected. It was found that the vast majority of patients underwent primary intervention up to 12 months of age. The surgical techniques used in the approach to this pathology showed an important chronological variation over the years. Discussion: Cleft lip and/or palate is a medical condition associated with high aesthetic and functional morbidity, which requires early treatment in order to optimize the long-term outcome. The existence of a nasolabial component and its respective surgical correction plays a central role in the treatment of this pathology. The high rates of post-surgical complications and unconvincing aesthetic results have motivated an evolution of the surgical technique, increasingly evident in recent years, allowing today to achieve satisfactory aesthetic results, even in bilateral cleft lip with high deformation complexity. The introduction of techniques that favor nasolabial reconstruction based on anatomical principles has been producing increasingly convincing results. The analyzed sample shows that most of the results obtained in this study are, in general, compatible with the results published in the literature. Conclusion: This work showed that the existence of small variations in the surgical technique can bring significant improvements in the functional and aesthetic results in the treatment of bilateral cleft lip.

Keywords: cleft lip, palate lip, congenital abnormalities, cranofacial malformations

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3437 Pale, Firm and Non-Exudative (PFN): An Emerging Major Broiler Breast Meat Group

Authors: Cintia Midori Kaminishikawahara, Fernanda Jéssica Mendonça, Moisés Grespan, Elza Iouko Ida, Massami Shimokomaki, Adriana Lourenço Soares

Abstract:

The quality of broiler breast meat is changing as a result of continuing emphasis on genetically bird’s selection for efficiently higher meat production. The consumer is experiencing a cooked product that is drier and less juicy when consumed. Breast meat has been classified as PSE (pale, soft, exudative), DFD (dark, firm, dry) and normal color meat. However, recently variations of this color have been observed and they are not in line with the specificity of the meat functional properties. Thus, the objective of this work was to report the finding of a new pale meat color group characterized as Pale, Firm and Non-exudative (PFN) based on its pH, color, meat functional properties and micro structural evaluation. Breast meat fillets samples (n=1045) from commercial line were classified into PSE (pH ≤5.8, L* ≥ 53.0), PFN (pH > 5.8 and L* ≥ 53.0) and Normal (pH >5.8 and L* < 53.0), based on pH and L* values. In sequence, a total of 30 samples of each group were analyzed for the water holding capacity (WHC) and shear force (SF). The incidence was 9.1% for PSE meat, 85.7% for PFN and 5.2% for Normal meat. The PSE meat presented lower values of WHC (P ≤ 0.05) followed in sequence by PFN and Normal samples and also the SF values of fresh PFN was higher than PSE meat (P ≤ 0.05) and similar to Normal samples. Under optical microscopy, the cell diameter was 10% higher for PFN in relation to PSE meat and similar to Normal meat. These preliminary results indicate an emerging group of breast meat and it should be considered that the Pale, Firm and Non-exudative should be considered as an ideal broiler breast meat quality.

Keywords: broiler PSE meat, light microscopy, texture, water holding capacity

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3436 Prototype Development of Knitted Buoyant Swimming Vest for Children

Authors: Nga-Wun Li, Chu-Po Ho, Kit-Lun Yick, Jin-Yun Zhou

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The use of buoyant vests incorporated with swimsuits can develop children’s confidence in the water, particularly for novice swimmers. Consequently, parents intend to purchase buoyant swimming vests for the children to reduce their anxiety to water. Although the conventional buoyant swimming vests can provide the buoyant function to the wearer, their bulkiness and hardness make children feel uncomfortable and not willing to wear. This study aimed to apply inlay knitting technology to design new functional buoyant swimming vests for children. This prototype involved a shell and a buoyant knitted layer, which is the main media to provide buoyancy. Polypropylene yarn and 6.4 mm of Expandable Polyethylene (EPE) foam were fabricated in Full needle stitch with inlay knitting technology and were then linked by sewing to form the buoyant layer. The shell of the knitted buoyant vest was made of Polypropylene circular knitted fabric. The structure of knitted fabrics of the buoyant swimsuit makes them inherently stretchable, and the arrangement of the inlaid material was designed based on the body movement that can improve the ease with which the swimmer moves. Further, the shoulder seam is designed at the back to minimize the irritation of the wearer. Apart from maintaining the buoyant function to them, this prototype shows its contribution in reducing bulkiness and improving softness to the conventional buoyant swimming vest by taking the advantages of a knitted garment. The results in this study are significant to the development of the buoyant swimming vest for both the textile and the fast-growing sportswear industry.

Keywords: knitting technology, buoyancy, inlay, swimming vest, functional garment

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3435 Landslide Hazard a Gigantic Problem in Indian Himalayan Region: Needs In-Depth Research to Minimize Disaster

Authors: Varun Joshi, M. S. Rawat

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The Indian Himalayan Region (IHR) is inherently fragile and susceptible to landslide hazard due to its extremely weak geology, highly rugged topography and heavy monsoonal rainfall. One of the most common hazards in the IHR is landslide, and this event is particularly frequent in Himalayan states of India i.e. Jammu & Kashmir, Himachal Pradesh, Uttarakhand, Sikkim, Manipur and Arunachal Pradesh. Landslides are mostly triggered by extreme rainfall events but the incidence increases during monsoon months (June to September). Natural slopes which are otherwise stable but they get destabilized due to anthropogenic activities like construction of various developmental activities and deforestation. These activities are required to fulfill the developmental needs and upliftment of societal status in the region. Landslides also trigger during major earthquakes and reported most observable and damaging phenomena. Studies indicate that the landslide phenomenon has increased many folds due to developmental activities in Himalayan region. Gradually increasing and devastating consequences of landslides turned into one of the most important hydro-geological hazards in Himalayan states especially in Uttarakhand and Sikkim states of India. The recent most catastrophic rainfall in June 2013 in Uttarakhand lead to colossal loss of life and property. The societal damage due to this incident is still to be recovered even after three years. Sikkim earthquake of September 2011 is witnessed for triggering of large number of coseismic landslides. The rescue and relief team faced huge problem in helping the trapped villagers in remote locations of the state due to road side blockade by landslides. The recent past incidences of landslides in Uttarakhand, as well as Sikkim states, created a new domain of research in terms of understanding the phenomena of landslide and management of disaster in such situation. Every year at many locations landslides trigger which force dwellers to either evacuate their dwelling or lose their life and property. The communication and transportation networks are also severely affected by landslides at several locations. Many times the drinking water supply disturbed and shortage of daily need household items reported during monsoon months. To minimize the severity of landslide in IHR requires in-depth research and developmental planning. For most of the areas in the present study, landslide hazard zonation is done on 1:50,000 scale. The land use planning maps on extensive basis are not available. Therefore, there is a need of large-scale landslide hazard zonation and land use planning maps. If the scientist conduct research on desired aspects and their outcome of research is utilized by the government in developmental planning then the incidents of landslide could be minimized, subsequent impact on society, life and property would be reduced. Along with the scientific research, there is another need of awareness generation in the region for stake holders and local dwellers to combat with the landslide hazard, if triggered in their location.

Keywords: coseismic, Indian Himalayan Region, landslide hazard zonation, Sikkim, societal, Uttarakhand

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3434 A Network of Nouns and Their Features :A Neurocomputational Study

Authors: Skiker Kaoutar, Mounir Maouene

Abstract:

Neuroimaging studies indicate that a large fronto-parieto-temporal network support nouns and their features, with some areas store semantic knowledge (visual, auditory, olfactory, gustatory,…), other areas store lexical representation and other areas are implicated in general semantic processing. However, it is not well understood how this fronto-parieto-temporal network can be modulated by different semantic tasks and different semantic relations between nouns. In this study, we combine a behavioral semantic network, functional MRI studies involving object’s related nouns and brain network studies to explain how different semantic tasks and different semantic relations between nouns can modulate the activity within the brain network of nouns and their features. We first describe how nouns and their features form a large scale brain network. For this end, we examine the connectivities between areas recruited during the processing of nouns to know which configurations of interaction areas are possible. We can thus identify if, for example, brain areas that store semantic knowledge communicate via functional/structural links with areas that store lexical representations. Second, we examine how this network is modulated by different semantic tasks involving nouns and finally, we examine how category specific activation may result from the semantic relations among nouns. The results indicate that brain network of nouns and their features is highly modulated and flexible by different semantic tasks and semantic relations. At the end, this study can be used as a guide to help neurosientifics to interpret the pattern of fMRI activations detected in the semantic processing of nouns. Specifically; this study can help to interpret the category specific activations observed extensively in a large number of neuroimaging studies and clinical studies.

Keywords: nouns, features, network, category specificity

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3433 Interaction Evaluation of Silver Ion and Silver Nanoparticles with Dithizone Complexes Using DFT Calculations and NMR Analysis

Authors: W. Nootcharin, S. Sujittra, K. Mayuso, K. Kornphimol, M. Rawiwan

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Silver has distinct antibacterial properties and has been used as a component of commercial products with many applications. An increasing number of commercial products cause risks of silver effects for human and environment such as the symptoms of Argyria and the release of silver to the environment. Therefore, the detection of silver in the aquatic environment is important. The colorimetric chemosensor is designed by the basic of ligand interactions with a metal ion, leading to the change of signals for the naked-eyes which are very useful method to this application. Dithizone ligand is considered as one of the effective chelating reagents for metal ions due to its high selectivity and sensitivity of a photochromic reaction for silver as well as the linear backbone of dithizone affords the rotation of various isomeric forms. The present study is focused on the conformation and interaction of silver ion and silver nanoparticles (AgNPs) with dithizone using density functional theory (DFT). The interaction parameters were determined in term of binding energy of complexes and the geometry optimization, frequency of the structures and calculation of binding energies using density functional approaches B3LYP and the 6-31G(d,p) basis set. Moreover, the interaction of silver–dithizone complexes was supported by UV–Vis spectroscopy, FT-IR spectrum that was simulated by using B3LYP/6-31G(d,p) and 1H NMR spectra calculation using B3LYP/6-311+G(2d,p) method compared with the experimental data. The results showed the ion exchange interaction between hydrogen of dithizone and silver atom, with minimized binding energies of silver–dithizone interaction. However, the result of AgNPs in the form of complexes with dithizone. Moreover, the AgNPs-dithizone complexes were confirmed by using transmission electron microscope (TEM). Therefore, the results can be the useful information for determination of complex interaction using the analysis of computer simulations.

Keywords: silver nanoparticles, dithizone, DFT, NMR

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3432 Short-Range and Long-Range Ferrimagnetic Order in Fe(Te₁.₅Se₀.₅)O₅Cl

Authors: E. S. Kozlyakova, A. A. Eliseev, A. V. Moskin, A. Y. Akhrorov, P. S. Berdonosov, V. A. Dolgikh, K. N. Denisova, P. Lemmens, B. Rahaman, S. Das, T. Saha-Dasgupta, A. N. Vasiliev, O. S. Volkova

Abstract:

Considerable attention has been paid recently to FeTe₂O₅Cl due to reduced dimensionality and frustration in the magnetic subsystem, succession of phase transitions, and multiferroicity. The efforts to grow its selenite sibling resulted in mixed halide compound, Fe(Te₁.₅Se₀.₅)O₅Cl, which was found crystallizing in a new structural type and possessing properties drastically different from those of a parent system. Hereby we report the studies of magnetization M and specific heat Cₚ, combined with Raman spectroscopy and density functional theory calculations in Fe(Te₁.₅Se₀.₅)O₅Cl. Its magnetic subsystem features weakly coupled Fe³⁺ - Fe³⁺ dimers showing the regime of short-range correlations at TM ~ 70 K and long-range order at TN = 22 K. In a magnetically ordered state, sizable spin-orbital interactions lead to a small canting of Fe³⁺ moments. The density functional theory calculations of leading exchange interactions were found in agreement with measurements of thermodynamic properties and Raman spectroscopy. Besides, because of the relatively large magnetic moment of the Fe³⁺ ion, we found that magnetic dipole-dipole interactions contribute significantly to experimentally observed orientation of magnetization easy axis in ac-plane. As a conclusion, we suggest a model of magnetic subsystem in magnetically ordered state of Fe(Te₁.₅Se₀.₅)O₅Cl based on a model of interacting dimers.

Keywords: dipole-dipole interactions, low dimensional magnetism, selenite, spin canting

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3431 Managing Polytechnic Education for Entrepreneurship Development in Nigeria

Authors: Oluwalola Felicia Kikelomo

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The introduction of entrepreneurship education in polytechnics is seen as a measure to reduce the rate of unemployment and strategically position the economy for sustainable development in Nigeria. This paper discusses the roles of polytechnics in entrepreneurship development. It also examines the challenges of entrepreneurship education in Polytechnics. The paper recommends, among others, that the entrepreneurship education should be property funded by the government with the support of non-governmental organizations so that there would be adequate resources to organize and manage the education. In addition, drastic and serious awareness campaigns should be mounted to sensitize the public and the students on the need for entrepreneurship education.

Keywords: education, polytechnic entrepreneurship development, education, human development

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3430 Performance Evaluation of a Small Microturbine Cogeneration Functional Model

Authors: Jeni A. Popescu, Sorin G. Tomescu, Valeriu A. Vilag

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The paper focuses on the potential methods of increasing the performance of a microturbine by combining additional elements available for utilization in a cogeneration plant. The activity is carried out within the framework of a project aiming to develop, manufacture and test a microturbine functional model with high potential in energetic industry utilization. The main goal of the analysis is to determine the parameters of the fluid flow passing through each section of the turbine, based on limited data available in literature for the focus output power range or provided by experimental studies, starting from a reference cycle, and considering different cycle options, including simple, intercooled and recuperated options, in order to optimize a small cogeneration plant operation. The studied configurations operate under the same initial thermodynamic conditions and are based on a series of assumptions, in terms of individual performance of the components, pressure/velocity losses, compression ratios, and efficiencies. The thermodynamic analysis evaluates the expected performance of the microturbine cycle, while providing a series of input data and limitations to be included in the development of the experimental plan. To simplify the calculations and to allow a clear estimation of the effect of heat transfer between fluids, the working fluid for all the thermodynamic evolutions is, initially, air, the combustion being modelled by simple heat addition to the system. The theoretical results, along with preliminary experimental results are presented, aiming for a correlation in terms of microturbine performance.

Keywords: cogeneration, microturbine, performance, thermodynamic analysis

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3429 The Urgenda and Juliana Cases: Redefining the Notion of Environmental Democracy

Authors: Valentina Dotto

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Climate change cases used to take the form of statutory disputes rather than constitutional or common law disputes. This changed in 2015, with the Urgenda Climate case in the Netherlands (Urgenda Foundation v. The State of the Netherlands, C/09/456689/HAZA 13-1396) and, the Juliana case in the U.S. (United States v. U.S. District Court for District of Oregon, 17-71692, 9th Cir.). The two cases represent a new type of climate litigation, the claims brought against the federal government were in fact grounded in constitutional rights. The complaints used the Doctrine of Public Trust as a cornerstone for the lawsuits asserting that government's actions against climate change failed to protect essential public trust resources; thus, violating a generation's constitutional rights to life, liberty, and property. The Public Trust Doctrine –a quintessentially American legal concept-, reserved to the States by virtue of the 9th and 10th amendment of the federal Constitution, gives them considerable jurisdiction over natural resources and has been refined by a number of Supreme Court rulings. The Juliana case exemplifies the Doctrine’s evolutionary nature because it attempts to apply it to the federal government, and establish a right to a climate system capable of sustaining human life as a fundamental right protected by a substantive due process. Furthermore, the flexibility of the Doctrine makes it permissible to be applied to a variety of different legal systems as in the Urgenda case. At the very heart of the lawsuits stands the question of who owns the Earth resources and, to what extent the general public can claim the services that the Earth provides as common property. By employing the widest possible definition of the Doctrine of Public Trust these lawsuits tried to redefine environmental resources as a collective right of all people. By doing case analysis, the paper explores how these cases can contribute to widening the public access to information and broadening the public voice in decision making as well as providing a precedent to equal access in seeking justice and redress from environmental failures.

Keywords: climate change, doctrine of public trust, environmental democracy, Juliana case, Urgenda climate case

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3428 Anticancer Effect of Doxorubicin Using Injectable Hydrogel

Authors: Prasamsha Panta, Da Yeon Kim, Ja Yong Jang, Min Jae Kim, Jae Ho Kim, Moon Suk Kim

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Introduction: Among the many anticancer drugs used clinically, doxorubicin (Dox), was one of widely used drugs to treat many types of solid tumors such as liver, colon, breast, or lung. Intratumoral injection of chemotherapeutic agents is a potentially more effective alternative to systemic administration because direct delivery of the anticancer drug to the target may improve both the stability and efficacy of anticancer drugs. Injectable in situ-forming gels have attracted considerable attention because they can achieve site specific drug delivery, long term action periods, and improved patient compliance. Objective: Objective of present study is to confirm clinical benefit of intratumoral chemotherapy using injectable in situ-forming poly(ethylene glycol)-b-polycaprolactone diblock copolymer (MP) and Dox with increase in efficacy and reducing the toxicity in patients with cancer diseases. Methods and methodology: We prepared biodegradable MP hydrogel and measured viscosity for the evaluation of thermo-sensitive property. In vivo antitumor activity was performed with normal saline, MP only, single free Dox, repeat free Dox, and Dox-loaded MP gel. The remaining amount of Dox drug was measured using HPLC after the mouse was sacrified. For cytotoxicity studies WST-1 assay was performed. Histological analysis was done with H&E and TUNEL processes respectively. Results: The works in this experiment showed that Dox-loaded MP have biodegradable drug depot property. Dox-loaded MP gels showed remarkable in vitro cytotoxicity activities against cancer cells. Finally, this work indicates that injection of Dox-loaded MP allowed Dox to act effectively in the tumor and induced long-lasting supression of tumor growth. Conclusion: This work has examined the potential clinical utility of intratumorally injected Dox-loaded MP gel, which shows significant effect of higher local Dox retention compared with systemically administered Dox.

Keywords: injectable in-situ forming hydrogel, anticancer, doxorubicin, intratumoral injection

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3427 Green Synthesis of Silver and Silver-Gold Alloy Nanoparticle Using Cyanobacteria as Bioreagent

Authors: Piya Roychoudhury, Ruma Pal

Abstract:

Cyanobacteria, commonly known as blue green algae were found to be an effective bioreagent for nanoparticle synthesis. Nowadays silver nanoparticles (AgNPs) are very popular due to their antimicrobial and anti-proliferative activity. To exploit these characters in different biotechnological fields, it is very essential to synthesize more stable, non-toxic nano-silver. For this reason silver-gold alloy (Ag-AuNPs) nanoparticles are of great interest as they are more stable, harder and more effective than single metal nanoparticles. In the present communication we described a simple technique for rapid synthesis of biocompatible AgNP and Ag-AuNP employing cyanobacteria, Leptolyngbya and Lyngbya respectively. For synthesis of AgNP the biomass of Leptolyngbya valderiana (200 mg Fresh weight) was exposed to 9 mM AgNO3 solution (pH 4). For synthesis of Ag-AuNP Lyngbya majuscula (200 mg Fresh weight) was exposed to equimolar solution of hydrogen tetra-auro chlorate and silver nitrate (1mM, pH 4). After 72 hrs of exposure thallus of Leptolyngyba turned brown in color and filaments of Lyngbya turned pink in color that indicated synthesis of nanoparticles. The produced particles were extracted from the cyanobacterial biomass using nano-capping agent, sodium citrate. Firstly, extracted brown and pink suspensions were taken for Energy Dispersive X-ray (EDAX) analysis to confirm the presence of silver in brown suspension and presence of both gold and silver in pink suspension. Extracted nanoparticles showed a distinct single plasmon band (AgNP at 411 nm; Ag-Au NP at 481 nm) in Uv-vis spectroscopy. It was revealed from Transmission electron microscopy (TEM) that all the synthesized particles were spherical in nature with a size range of ~2-25 nm. In X-ray powder diffraction (XRD) analysis four intense peaks appeared at 38.2°, 44.5°, 64.8°and 77.8° which confirmed the crystallographic nature of synthesized particles. Presence of different functional groups viz. N-H, C=C, C–O, C=O on the surface of nanoparticles were recorded by Fourier transform infrared spectroscopy (FTIR). Scanning Electron microscopy (SEM) images showed the surface topography of metal treated filaments of cyanobacteria. The stability of the particles was observed by Zeta potential study. Antibiotic property of synthesized particles was tested by Agar well diffusion method against gram negative bacteria Pseudomonas aeruginosa. Overall, this green-technique requires low energy, less manufacturing cost and produces rapidly eco-friendly metal nanoparticles.

Keywords: cyanobacteria, silver nanoparticles, silver-gold alloy nanoparticles, spectroscopy

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3426 Chemical Composition, in vitro Antioxidant Activity and Gas Chromatography–Mass Spectrometry Analysis of Essential Oil and Extracts of Ruta chalpensis aerial Parts Growing in Tunisian Sahara

Authors: Samir Falhi, Neji Gharsallah, Adel Kadri

Abstract:

Ruta chalpensis L. is a medicinal plant in the family of Rutaceae, has been used as an important traditional in the Mediterranean basin in the treatment of many diseases. The current study was devoted to investigate and evaluate the chemical composition, total phenolic, flavonoid and tannin contents, and in vitro antioxidant activities of ethyl acetate, ethanol and hydroalcoholic extracts and essential oil from the aerial parts of Ruta chalpensis from Tunisian Sahara. Total phenolic, flavonoid and tannin contents of extracts ranged from 40.39 ± 1.87 to 75.13 ± 1.22 mg of GAE/g, from 22.62 ± 1.55 to 27.51 ± 1.04 mg of QE/g, and from 5.56 ± 1.32 to 10.89 ± 1.10 mg of CE/g respectively. Results showed that the highest antioxidant activities was determined for ethanol extract with IC50 value of 26.23 ± 0.91 µg/mL for 2,2-diphenyl-1-picrylhydrazyl assay, and for hydroalcoholic extract with EC50 value of 412.95±6.57 µg/mL and 105.52±2.45 mg of α-tocopherol/g for ferric reducing antioxidant power and total antioxidant capacity assays, respectively. Furthermore, Gas Chromatography–Mass Spectrometry (GC-MS) analysis of essential oil led to identification of 20 compounds representing 98.96 % of the total composition. The major components of essential oil were 2-undecanone (39.13%), 2-nonanone (25.04), 1-nonene (13.81), and α-limonene (7.72). Spectral data of Fourier-transform infrared spectroscopy analysis (FT-IR) of extracts revealed the presence of functional groups such as C= O, C─O, ─OH, and C─H, which confirmed its richness on polyphenols and biological active functional groups. These results showed that Ruta chalpensis could be a potential natural source of antioxidants that can be used in food and nutraceutical applications.

Keywords: antioxidant, FT-IR analysis, GC-MS analysis, phytochemicals contents, Ruta chalpensis

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3425 A New Modification of Nonlinear Conjugate Gradient Coefficients with Global Convergence Properties

Authors: Ahmad Alhawarat, Mustafa Mamat, Mohd Rivaie, Ismail Mohd

Abstract:

Conjugate gradient method has been enormously used to solve large scale unconstrained optimization problems due to the number of iteration, memory, CPU time, and convergence property, in this paper we find a new class of nonlinear conjugate gradient coefficient with global convergence properties proved by exact line search. The numerical results for our new βK give a good result when it compared with well-known formulas.

Keywords: conjugate gradient method, conjugate gradient coefficient, global convergence

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3424 A Linear Regression Model for Estimating Anxiety Index Using Wide Area Frontal Lobe Brain Blood Volume

Authors: Takashi Kaburagi, Masashi Takenaka, Yosuke Kurihara, Takashi Matsumoto

Abstract:

Major depressive disorder (MDD) is one of the most common mental illnesses today. It is believed to be caused by a combination of several factors, including stress. Stress can be quantitatively evaluated using the State-Trait Anxiety Inventory (STAI), one of the best indices to evaluate anxiety. Although STAI scores are widely used in applications ranging from clinical diagnosis to basic research, the scores are calculated based on a self-reported questionnaire. An objective evaluation is required because the subject may intentionally change his/her answers if multiple tests are carried out. In this article, we present a modified index called the “multi-channel Laterality Index at Rest (mc-LIR)” by recording the brain activity from a wider area of the frontal lobe using multi-channel functional near-infrared spectroscopy (fNIRS). The presented index aims to measure multiple positions near the Fpz defined by the international 10-20 system positioning. Using 24 subjects, the dependencies on the number of measuring points used to calculate the mc-LIR and its correlation coefficients with the STAI scores are reported. Furthermore, a simple linear regression was performed to estimate the STAI scores from mc-LIR. The cross-validation error is also reported. The experimental results show that using multiple positions near the Fpz will improve the correlation coefficients and estimation than those using only two positions.

Keywords: frontal lobe, functional near-infrared spectroscopy, state-trait anxiety inventory score, stress

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3423 O-Functionalized CNT Mediated CO Hydro-Deoxygenation and Chain Growth

Authors: K. Mondal, S. Talapatra, M. Terrones, S. Pokhrel, C. Frizzel, B. Sumpter, V. Meunier, A. L. Elias

Abstract:

Worldwide energy independence is reliant on the ability to leverage locally available resources for fuel production. Recently, syngas produced through gasification of carbonaceous materials provided a gateway to a host of processes for the production of various chemicals including transportation fuels. The basis of the production of gasoline and diesel-like fuels is the Fischer Tropsch Synthesis (FTS) process: A catalyzed chemical reaction that converts a mixture of carbon monoxide (CO) and hydrogen (H2) into long chain hydrocarbons. Until now, it has been argued that only transition metal catalysts (usually Co or Fe) are active toward the CO hydrogenation and subsequent chain growth in the presence of hydrogen. In this paper, we demonstrate that carbon nanotube (CNT) surfaces are also capable of hydro-deoxygenating CO and producing long chain hydrocarbons similar to that obtained through the FTS but with orders of magnitude higher conversion efficiencies than the present state-of-the-art FTS catalysts. We have used advanced experimental tools such as XPS and microscopy techniques to characterize CNTs and identify C-O functional groups as the active sites for the enhanced catalytic activity. Furthermore, we have conducted quantum Density Functional Theory (DFT) calculations to confirm that C-O groups (inherent on CNT surfaces) could indeed be catalytically active towards reduction of CO with H2, and capable of sustaining chain growth. The DFT calculations have shown that the kinetically and thermodynamically feasible route for CO insertion and hydro-deoxygenation are different from that on transition metal catalysts. Experiments on a continuous flow tubular reactor with various nearly metal-free CNTs have been carried out and the products have been analyzed. CNTs functionalized by various methods were evaluated under different conditions. Reactor tests revealed that the hydrogen pre-treatment reduced the activity of the catalysts to negligible levels. Without the pretreatment, the activity for CO conversion as found to be 7 µmol CO/g CNT/s. The O-functionalized samples showed very activities greater than 85 µmol CO/g CNT/s with nearly 100% conversion. Analyses show that CO hydro-deoxygenation occurred at the C-O/O-H functional groups. It was found that while the products were similar to FT products, differences in selectivities were observed which, in turn, was a result of a different catalytic mechanism. These findings now open a new paradigm for CNT-based hydrogenation catalysts and constitute a defining point for obtaining clean, earth abundant, alternative fuels through the use of efficient and renewable catalyst.

Keywords: CNT, CO Hydrodeoxygenation, DFT, liquid fuels, XPS, XTL

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3422 Strength Parameters and the Rate Process Theory Applied to Compacted Fadama Soils

Authors: Samuel Akinlabi Ola, Emeka Segun Nnochiri, Stephen Kayode Aderomose, Paul Ayesemhe Edoh

Abstract:

Fadama soils of Northern Nigeria are generally a problem soil for highway and geotechnical engineers. There has been no consistent conclusion on the effect of the strain rate on the shear strength of soils, thus necessitating the need to clarify this issue with various types of soil. Consolidated undrained tests with pore pressure measurements were conducted at optimum moisture content and maximum dry density using standard proctor compaction. Back pressures were applied to saturate the soil. The shear strength parameters were determined. Analyzing the results and model studies using the Rate Process Theory, functional relationships between the deviator stress and strain rate were determined and expressed mathematically as deviator stress = β0+ β1 log(strain rate) at each cell pressure where β0 and β1 are constants. Also, functional relationships between the pore pressure coefficient Āf and the time to failure were determined and expressed mathematically as pore pressure coefficient, Āf = ψ0+ѱ1log (time to failure) where ψ0 and ѱ1 are constants. For cell pressure between 69 – 310 kN/m2 (10 - 45psi) the constants found for Fadama soil in this study are ψ0=0.17 and ѱ1=0.18. The study also shows the dependence of the angle of friction (ø’) on the rate of strain as it increases from 22o to 25o for an increase in the rate of strain from 0.08%/min to 1.0%/min. Conclusively, the study also shows that within the strain rate utilized in the research, the deviator strength increased with the strain rate while the excess pore water pressure decreased with an increase in the rate of strain.

Keywords: deviator stress, Fadama soils, pore pressure coefficient, rate process

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3421 Comparison of Mechanical Property of UNS C12200Joints Brazed by (Cu&Ag) Based Filler Metals

Authors: Ali Elhatmi, Mustafa Elshbo, Hussin Alosta

Abstract:

In this study the coper tube witch used in medical applications was brazed by Copper, Zink and Silver alloys, using BCuP2, RBCuZnAl and BAg2 filler metals. The sample of the medical tubes was chemically analyzed and the result matches the British standard. Tensile and hardness tests were carried out for brazed joints, and the tensile test results show that the BCuP2 has the hardest and the filler metal RBCuZnAl has the highest tensile strength.

Keywords: welding, Brazing, Copper tubes, Joints

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3420 Development of Methods for Plastic Injection Mold Weight Reduction

Authors: Bita Mohajernia, R. J. Urbanic

Abstract:

Mold making techniques have focused on meeting the customers’ functional and process requirements; however, today, molds are increasing in size and sophistication, and are difficult to manufacture, transport, and set up due to their size and mass. Presently, mold weight saving techniques focus on pockets to reduce the mass of the mold, but the overall size is still large, which introduces costs related to the stock material purchase, processing time for process planning, machining and validation, and excess waste materials. Reducing the overall size of the mold is desirable for many reasons, but the functional requirements, tool life, and durability cannot be compromised in the process. It is proposed to use Finite Element Analysis simulation tools to model the forces, and pressures to determine where the material can be removed. The potential results of this project will reduce manufacturing costs. In this study, a light weight structure is defined by an optimal distribution of material to carry external loads. The optimization objective of this research is to determine methods to provide the optimum layout for the mold structure. The topology optimization method is utilized to improve structural stiffness while decreasing the weight using the OptiStruct software. The optimized CAD model is compared with the primary geometry of the mold from the NX software. Results of optimization show an 8% weight reduction while the actual performance of the optimized structure, validated by physical testing, is similar to the original structure.

Keywords: finite element analysis, plastic injection molding, topology optimization, weight reduction

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3419 Feeling Sorry for Some Creditors

Authors: Hans Tjio, Wee Meng Seng

Abstract:

The interaction of contract and property has always been a concern in corporate and commercial law, where there are internal structures created that may not match the externally perceived image generated by the labels attached to those structures. We will focus, in particular, on the priority structures created by affirmative asset partitioning, which have increasingly come under challenge by those attempting to negotiate around them. The most prominent has been the AT1 bonds issued by Credit Suisse which were wiped out before its equity when the troubled bank was acquired by UBS. However, this should not have come as a surprise to those whose “bonds” had similarly been “redeemed” upon the occurrence of certain reference events in countries like Singapore, Hong Kong and Taiwan during their Minibond crisis linked to US sub-prime defaults. These were derivatives classified as debentures and sold as such. At the same time, we are again witnessing “liabilities” seemingly ranking higher up the balance sheet ladder, finding themselves lowered in events of default. We will examine the mechanisms holders of perpetual securities or preference shares have tried to use to protect themselves. This is happening against a backdrop that sees a rise in the strength of private credit and inter-creditor conflicts. The restructuring regime of the hybrid scheme in Singapore now, while adopting the absolute priority rule in Chapter 11 as the quid pro quo for creditor cramdown, does not apply to shareholders and so exempts them from cramdown. Complicating the picture further, shareholders are not exempted from cramdown in the Dutch scheme, but it adopts a relative priority rule. At the same time, the important UK Supreme Court decision in BTI 2014 LLC v Sequana [2022] UKSC 25 has held that directors’ duties to take account of creditor interests are activated only when a company is almost insolvent. All this has been complicated by digital assets created by businesses. Investors are quite happy to have them classified as property (like a thing) when it comes to their transferability, but then when the issuer defaults to have them seen as a claim on the business (as a choice in action), that puts them at the level of a creditor. But these hidden interests will not show themselves on an issuer’s balance sheet until it is too late to be considered and yet if accepted, may also prevent any meaningful restructuring.

Keywords: asset partitioning, creditor priority, restructuring, BTI v Sequana, digital assets

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3418 Open Innovation for Crowdsourced Product Development: The Case Study of Quirky.com

Authors: Ana Bilandzic, Marcus Foth, Greg Hearn

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In a narrow sense, innovation is the invention and commercialisation of a new product or service in the marketplace. The literature suggests places that support knowledge exchange and social interaction, e.g. coffee shops, to nurture innovative ideas. With the widespread success of Internet, interpersonal communication and interaction changed. Online platforms complement physical places for idea exchange and innovation – the rise of hybrid, ‘net localities.’ Further, since its introduction in 2003 by Chesbrough, the concept of open innovation received increased attention as a topic in academic research as well as an innovation strategy applied by companies. Open innovation allows companies to seek and release intellectual property and new ideas from outside of their own company. As a consequence, the innovation process is no longer only managed within the company, but it is pursued in a co-creation process with customers, suppliers, and other stakeholders. Quirky.com (Quirky), a company founded by Ben Kaufman in 2009, recognised the opportunity given by the Internet for knowledge exchange and open innovation. Quirky developed an online platform that makes innovation available to everyone. This paper reports on a study that analysed Quirky’s business process in an extended event-driven process chain (eEPC). The aim was to determine how the platform enabled crowdsourced innovation for physical products on the Internet. The analysis reveals that key elements of the business model are based on open innovation. Quirky is an example of how open innovation can support crowdsourced and crowdfunded product ideation, development and selling. The company opened up various stages in the innovation process to its members to contribute in the product development, e.g. product ideation, design, and market research. Throughout the process, members earn influence through participating in the product development. Based on the influence they receive, shares on the product’s turnover. The outcomes of the study’s analysis highlighted certain benefits of open innovation for product development. The paper concludes with recommendations for future research to look into opportunities of open innovation approaches to be adopted by tertiary institutions as a novel way to commercialise research intellectual property.

Keywords: business process, crowdsourced innovation, open innovation, Quirky

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3417 Understanding the Challenges of Lawbook Translation via the Framework of Functional Theory of Language

Authors: Tengku Sepora Tengku Mahadi

Abstract:

Where the speed of book writing lags behind the high need for such material for tertiary studies, translation offers a way to enhance the equilibrium in this demand-supply equation. Nevertheless, translation is confronted by obstacles that threaten its effectiveness. The primary challenge to the production of efficient translations may well be related to the text-type and in terms of its complexity. A text that is intricately written with unique rhetorical devices, subject-matter foundation and cultural references will undoubtedly challenge the translator. Longer time and greater effort would be the consequence. To understand these text-related challenges, the present paper set out to analyze a lawbook entitled Learning the Law by David Melinkoff. The book is chosen because it has often been used as a textbook or for reference in many law courses in the United Kingdom and has seen over thirteen editions; therefore, it can be said to be a worthy book for studies in law. Another reason is the existence of a ready translation in Malay. Reference to this translation enables confirmation to some extent of the potential problems that might occur in its translation. Understanding the organization and the language of the book will help translators to prepare themselves better for the task. They can anticipate the research and time that may be needed to produce an effective translation. Another premise here is that this text-type implies certain ways of writing and organization. Accordingly, it seems practicable to adopt the functional theory of language as suggested by Michael Halliday as its theoretical framework. Concepts of the context of culture, the context of situation and measures of the field, tenor and mode form the instruments for analysis. Additional examples from similar materials can also be used to validate the findings. Some interesting findings include the presence of several other text-types or sub-text-types in the book and the dependence on literary discourse and devices to capture the meanings better or add color to the dry field of law. In addition, many elements of culture can be seen, for example, the use of familiar alternatives, allusions, and even terminology and references that date back to various periods of time and languages. Also found are parts which discuss origins of words and terms that may be relevant to readers within the United Kingdom but make little sense to readers of the book in other languages. In conclusion, the textual analysis in terms of its functions and the linguistic and textual devices used to achieve them can then be applied as a guide to determine the effectiveness of the translation that is produced.

Keywords: functional theory of language, lawbook text-type, rhetorical devices, culture

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3416 Advanced Magnetic Resonance Imaging in Differentiation of Neurocysticercosis and Tuberculoma

Authors: Rajendra N. Ghosh, Paramjeet Singh, Niranjan Khandelwal, Sameer Vyas, Pratibha Singhi, Naveen Sankhyan

Abstract:

Background: Tuberculoma and neurocysticercosis (NCC) are two most common intracranial infections in developing country. They often simulate on neuroimaging and in absence of typical imaging features cause significant diagnostic dilemmas. Differentiation is extremely important to avoid empirical exposure to antitubercular medications or nonspecific treatment causing disease progression. Purpose: Better characterization and differentiation of CNS tuberculoma and NCC by using morphological and multiple advanced functional MRI. Material and Methods: Total fifty untreated patients (20 tuberculoma and 30 NCC) were evaluated by using conventional and advanced sequences like CISS, SWI, DWI, DTI, Magnetization transfer (MT), T2Relaxometry (T2R), Perfusion and Spectroscopy. rCBV,ADC,FA,T2R,MTR values and metabolite ratios were calculated from lesion and normal parenchyma. Diagnosis was confirmed by typical biochemical, histopathological and imaging features. Results: CISS was most useful sequence for scolex detection (90% on CISS vs 73% on routine sequences). SWI showed higher scolex detection ability. Mean values of ADC, FA,T2R from core and rCBV from wall of lesion were significantly different in tuberculoma and NCC (P < 0.05). Mean values of rCBV, ADC, T2R and FA for tuberculoma and NCC were (3.36 vs1.3), (1.09x10⁻³vs 1.4x10⁻³), (0.13 x10⁻³ vs 0.09 x10⁻³) and (88.65 ms vs 272.3 ms) respectively. Tuberculomas showed high lipid peak, more choline and lower creatinine with Ch/Cr ratio > 1. T2R value was most significant parameter for differentiation. Cut off values for each significant parameters have proposed. Conclusion: Quantitative MRI in combination with conventional sequences can better characterize and differentiate similar appearing tuberculoma and NCC and may be incorporated in routine protocol which may avoid brain biopsy and empirical therapy.

Keywords: advanced functional MRI, differentiation, neurcysticercosis, tuberculoma

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3415 Amplitude Versus Offset (AVO) Modeling as a Tool for Seismic Reservoir Characterization of the Semliki Basin

Authors: Hillary Mwongyera

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The Semliki basin has become a frontier for petroleum exploration in recent years. Exploration efforts have resulted into extensive seismic data acquisition and drilling of three wells namely; Turaco 1, Turaco 2 and Turaco 3. A petrophysical analysis of the Turaco 1 well was carried out to identify two reservoir zones on which AVO modeling was performed. A combination of seismic modeling and rock physics modeling was applied during reservoir characterization and monitoring to determine variations of seismic responses with amplitude characteristics. AVO intercept gradient analysis applied on AVO synthetic CDP gathers classified AVO anomalies associated with both reservoir zones as Class 1 AVO anomalies. Fluid replacement modeling was carried out on both reservoir zones using homogeneous mixing and patchy saturation patterns to determine effects of fluid substitution on rock property interactions. For both homogeneous mixing and saturation patterns, density (ρ) showed an increasing trend with increasing brine substitution while Shear wave velocity (Vs) decreased with increasing brine substitution. A study of compressional wave velocity (Vp) with increasing brine substitution for both homogeneous mixing and patchy saturation gave quite interesting results. During patchy saturation, Vp increased with increasing brine substitution. During homogeneous mixing however, Vp showed a slightly decreasing trend with increasing brine substitution but increased tremendously towards and at full brine saturation. A sensitivity analysis carried out showed that density was a very sensitive rock property responding to brine saturation except at full brine saturation during homogeneous mixing where Vp showed greater sensitivity with brine saturation. Rock physics modeling was performed to predict diagnostics of reservoir quality using an inverse deterministic approach which showed low shale content and a high degree of shale stiffness within reservoir zones.

Keywords: Amplitude Versus Offset (AVO), fluid replacement modelling, reservoir characterization, AVO attributes, rock physics modelling, reservoir monitoring

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3414 Electrochemical and Microstructure Properties of Chromium-Graphene and SnZn-Graphene Oxide Composite Coatings

Authors: Rekha M. Y., Punith Kumar, Anshul Kamboj, Chandan Srivastava

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Coatings plays an important role in providing protection for a substrate and in improving the surface quality. Graphene/graphene oxide (GO) using in coating systems provides an environmental friendly solution towards protection against corrosion. Issues such as, lack of scale, high cost, low quality limits the practical application of graphene/GO as corrosion resistant coating material. One other way to employ these materials for corrosion protection is to incorporate them into coatings that are conventionally used for corrosion protection. Due to the extraordinary properties of graphene/GO, it has been demonstrated that the coatings containing graphene/GO are more corrosion resistant than pure metal/alloy coatings. In the present work, Cr-graphene and SnZn-GO composite coatings were investigated in enhancing the corrosion resistant property when compared to pure Cr coating and pure SnZn coating respectively. All the coatings were electrodeposited over mild-steel substrate. Graphene and GO were synthesized by electrochemical exfoliation method and modified Hummers’ method respectively. In Cr coatings, the microstructural study revealed that the addition of formic acid in the coatings reduced the number of cracks in the coatings. Further addition of graphene in Cr coating enhanced the Cr coating’s morphology. Chemically synthesized ZnO nanoparticles were also embedded in the as-deposited Cr and Cr-graphene coatings to enhance the adhesion of the coating, to improve the surface finish and to increase the corrosion resistant property of the coatings. Diffraction analysis revealed that the addition of graphene also altered the texture of the Cr coatings. In SnZn alloy coatings, the morphological and topographical characterization revealed that the relative smoothness and compactness of the coatings increased with increase in the addition of GO in the coatings. The microstructural investigation revealed large-scale segregation of Zn-rich and Sn-rich phases in the pure SnZn coating. However, in SnZn-GO composite coating the uniform distribution of Zn phase in the Sn-rich matrix was observed. This distribution caused the early and uniform formation of ZnO, which is the corrosion product, yielding better corrosion resistance for the SnZn-GO composite coatings as compared to pure SnZn coating. A significant improvement in corrosion resistance in terms of reduction in corrosion current and corrosion rate and increase in the polarization resistance was observed in Cr coating containing graphene and in SnZn coatings containing GO.

Keywords: coatings, corrosion, electrodeposition, graphene, graphene-oxide

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