Search results for: high dose rate brachytherapy
Commenced in January 2007
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Edition: International
Paper Count: 25670

Search results for: high dose rate brachytherapy

16940 Refractory Visceral Leishmaniasis Responding to Second-Line Therapy

Authors: Preet Shah, Om Shrivastav

Abstract:

Introduction : In India, Leishmania donovani is the only parasite causing Leishmaniasis. The parasite infects the reticuloendothelial system and is found in the bone marrow, spleen and liver. Treatment of choice is amphotericin-B with sodium stibogluconate being an alternative. Miltefosine is useful in refractory cases. In our case, Leishmaniasis occurred in a person residing in western India (which is quite rare) and it failed to respond to two different drugs (again an uncommon feature) before it finally responded to a third one. Description: A 50 year old lady, a resident of western India, with no history of recent travel, presented with an ulcer on the left side of the nose since 8 months. She was apparently alright 8 months back, when she noticed a small ulcerated lesion on the left ala of the nose which was immediately biopsied. The biopsy revealed amastigotes of Leishmania for which she was administered intra-lesional sodium stibogluconate for 1 month (4 doses every 8 days).Despite this, there was no regression of the ulcer and hence she presented to us for further management. On examination, her vital parameters were normal. Barring an ulcer on the left side of the nose, rest of the examination findings were unremarkable. Complete blood count was normal. Ultrasound abdomen showed hepatomegaly. PET-CT scan showed increased metabolic activity in left ala of nose, hepatosplenomegaly and increased metabolic activity in spleen and bone marrow. Bone marrow biopsy was done which showed hypercellular marrow with erythroid preponderance. Considering a diagnosis of leishmaniasis which had so far been unresponsive to sodium stibogluconate, she was started on liposomal amphotericin-B. At the time of admission, her creatinine level was normal, but it started rising with the administration of liposomal amphotericin-B, hence the dose was reduced. Despite this, creatinine levels did not improve, and she started developing hypokalemia and hypomagnesemia as side effects of the drug, hence further reductions in the dosage were made. Despite a total of 3 weeks of liposomal amphotericin-B, there was no improvement in the ulcer. As had so far failed to respond to sodium stibogluconate and liposomal amphotericin-B, it was decided to start her on miltefosine. She received the miltefosine for a total of 12 weeks. At the end of this duration, there was a marked regression of the cutaneous lesion. Conclusion: Refractoriness to amphotericin-B in leishmaniasis may be seen in up to 5 % cases. Here, an alternative drug such as miltefosine is useful and hence we decided to use it, to which she responded adequately. Furthermore, although leishmaniasis is common in the eastern part of India, it is a relatively unknown entity in the western part of the country with the occurrence being very rare. Because of these 2 reasons, we consider our case to be a unique one.

Keywords: amphotericin-b, leishmaniasis, miltefosine, tropical diseases

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16939 A Study on the Stabilization of the Swell Behavior of Basic Oxygen Furnace Slag by Using Geopolymer Technology

Authors: K. Y. Lin, W. H. Lee, T. W. Cheng, S. W. Huang

Abstract:

Basic Oxygen Furnace (BOF) Slag is a by-product of iron making. It has great engineering properties, such as, high hardness and density, high compressive strength, low abrasion ratio, and can replace natural aggregate for building materials. However, the main problem for BOF slag is expansion, due to it contains free lime or free magnesium. The purpose of this study was to stabilize the BOF slag by using geopolymeric technology, hoping can prevent BOF slag expansion. Geopolymer processes contain a large amount of free silicon. These free silicon can react with free-lime or free magnesium oxide in BOF slag, and thus to form stable compound, therefore inhibit the expansion of the BOF slag. In this study for the successful preparation of geopolymer mortar with BOF slag, and their main properties are analyzed with regard to their use as building materials. Autoclave is used to study the volume stability of these geopolymer mortar. Finally, the compressive strength of geopolymer mortar with BOF slag can be reached 33MPa in 28 days. After autoclave testing, the volume expansion does not exceed 0.2%. Even after the autoclave test, the compressive strength can increase to 35MPa. According to the research results can be proved that using geopolymer technology for stabilizing BOF slag is very effective.

Keywords: BOF slag, autoclave test, geopolymer, swell behavior

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16938 Detailed Depositional Resolutions in Upper Miocene Sands of HT-3X Well, Nam Con Son Basin, Vietnam

Authors: Vo Thi Hai Quan

Abstract:

Nam Con Son sedimentary basin is one of the very important oil and gas basins in offshore Vietnam. Hai Thach field of block 05-2 contains mostly gas accumulations in fine-grained, sand/mud-rich turbidite system, which was deposited in a turbidite channel and fan environment. Major Upper Miocene reservoir of HT-3X lies above a well-developed unconformity. The main objectives of this study are to reconstruct depositional environment and to assess the reservoir quality using data from 14 meters of core samples and digital wireline data of the well HT-3X. The wireline log and core data showed that the vertical sequences of representative facies of the well mainly range from Tb to Te divisions of Bouma sequences with predominance of Tb and Tc compared to Td and Te divisions. Sediments in this well were deposited in a submarine fan association with very fine to fine-grained, homogeneous sandstones that have high porosity and permeability, high- density turbidity currents with longer transport route from the sediment source to the basin, indicating good quality of reservoir. Sediments are comprised mainly of the following sedimentary structures: massive, laminated sandstones, convoluted bedding, laminated ripples, cross-laminated ripples, deformed sandstones, contorted bedding.

Keywords: Hai Thach field, Miocene sand, turbidite, wireline data

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16937 Using Closed Frequent Itemsets for Hierarchical Document Clustering

Authors: Cheng-Jhe Lee, Chiun-Chieh Hsu

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Due to the rapid development of the Internet and the increased availability of digital documents, the excessive information on the Internet has led to information overflow problem. In order to solve these problems for effective information retrieval, document clustering in text mining becomes a popular research topic. Clustering is the unsupervised classification of data items into groups without the need of training data. Many conventional document clustering methods perform inefficiently for large document collections because they were originally designed for relational database. Therefore they are impractical in real-world document clustering and require special handling for high dimensionality and high volume. We propose the FIHC (Frequent Itemset-based Hierarchical Clustering) method, which is a hierarchical clustering method developed for document clustering, where the intuition of FIHC is that there exist some common words for each cluster. FIHC uses such words to cluster documents and builds hierarchical topic tree. In this paper, we combine FIHC algorithm with ontology to solve the semantic problem and mine the meaning behind the words in documents. Furthermore, we use the closed frequent itemsets instead of only use frequent itemsets, which increases efficiency and scalability. The experimental results show that our method is more accurate than those of well-known document clustering algorithms.

Keywords: FIHC, documents clustering, ontology, closed frequent itemset

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16936 Preliminary Prospecting on the Distribution of the Disease of Citrus Tristeza Orchards in the Province of Chlef

Authors: Ibrahim Djelloul Berkane

Abstract:

A survey was conducted to assess the presence of the virus in Citrus tristeza one of the main citrus regions of Algeria, namely the Chlef region, using the technique of Direct Tissue Print Immunoprinting Assay (DTBIA) and the Double Sandwich ELISA antibodies. A nursery citrus, lumber yards, and commercial orchards, which are the main varieties cultivated citrus were subjected to samples collected samples for laboratory analysis. 0.91% of the plants tested orchards were infected with CTV, while no positive case was detected at the nursery the yard, however, it is reported that an alarming rate of 10,5% of orchards tested at the common Chettia were infected with tristeza virus. The investigation was launched to identify the vector species tristeza revealed the presence of a vector is important Aphis gossypii.

Keywords: aphis, chlef, citrus, DAS-ELISA, DTBIA, tristeza

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16935 Investigating University Students' Attitudes towards Infertility in Terms of Socio-Demographic Variables

Authors: Yelda Kağnıcı, Seçil Seymenler, Bahar Baran, Erol Esen, Barışcan Öztürk, Ender Siyez, Diğdem M. Siyez

Abstract:

Infertility is the inability to reproduce after twelve months or longer unprotected sexual relationship. Although infertility is not a life threatening illness, it is considered as a serious problem for both the individual and the society. At this point, the importance of examining attitudes towards infertility is critical. Negative attitudes towards infertility may postpone individuals’ help seeking behaviors. The aim of this study is to investigate university students’ attitudes towards infertility in terms of socio-demographic variables (gender, age, taking sexual health education, existence of an infertile individual in the social network, plans about having child and behaviors about health). The sample of the study was 9693 university students attending to 21 universities in Turkey. Of the 9693 students, % 51.6 (n = 5002) were female, % 48.4 (n = 4691) were male. The data was collected by Attitudes toward Infertility Scale developed by researchers and Personal Information Form. In data analysis first frequencies were calculated, then in order to test whether there were significant differences in attitudes towards infertility scores of university students in terms of socio-demographic variables, one way ANOVA was conducted. According to the results, it was found that female students, students who had sexual health education, who have sexual relationship experience, who have an infertile individual in their social networks, who have child plans, who have high caffeine usage and who use alcohol regularly have more positive attitudes towards infertility. On the other hand, attitudes towards infidelity did not show significant differences in terms of age and cigarette usage. When the results of the study were evaluated in general, it was seen that university students’ attitudes towards infertility were negative. The attitudes of students who have high caffeine and alcohols usage were high. It can be considered that these students are aware that their social habits are risky. Female students’ positive attitudes might be explained by their gender role. The results point out that in order to decrease university students’ negative attitudes towards infertility, there is a necessity to develop preventive programs in universities.

Keywords: infertility, attitudes, sex, university students

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16934 The Effect of the Construction Contract System by Simulating the Comparative Costs of Capital to the Financial Feasibility of the Construction of Toll Bali Mandara

Authors: Mas Pertiwi I. G. AG Istri, Sri Kristinayanti Wayan, Oka Aryawan I. Gede Made

Abstract:

Ability of government to meet the needs of infrastructure investment constrained by the size of the budget commitments for other sectors. Another barrier is the complexity of the process of land acquisition. Public Private Partnership can help bridge the investment gap by including the amount of funding from the private sector, shifted the responsibility of financing, construction of the asset, and the operation and post-project design and care to them. In principle, a construction project implementation always requires the investor as a party to provide resources in the form of funding which it must be contained in a successor agreement in the form of a contract. In general, construction contracts consist of contracts which passed in Indonesia and contract International. One source of funding used in the implementation of construction projects comes from funding that comes from the collaboration between the government and the private sector, for example with the system: BLT (Build Lease Transfer), BOT (Build Operate Transfer), BTO (Build Transfer Operate) and BOO (Build Operate Own). And form of payment under a construction contract can be distinguished several ways: monthly payment, payments based on progress and payment after completed projects (Turn Key). One of the tools used to analyze the feasibility of the investment is to use financial models. The financial model describes the relationship between different variables and assumptions used. From a financial model will be known how the cash flow structure of the project, which includes revenues, expenses, liabilities to creditors and the payment of taxes to the government. Net cash flow generated from the project will be used as a basis for analyzing the feasibility of investment source of project financing Public Private Partnership could come from equity or debt. The proportion of funding according to its source is a comparison of a number of investment funds originating from each source of financing for a total investment cost during the construction period by selected the contract system and several alternative financing percentage ratio determined according to sources will generate cash flow structure that is different. Of the various possibilities for the structure of the cash flow generated will be analyzed by software is to test T Paired to compared the contract system used by various alternatives comparison of financing to determine the effect of the contract system and the comparison of such financing for the feasibility of investment toll road construction project for the economic life of 20 (twenty) years. In this use case studies of toll road contruction project Bali Mandara. And in this analysis only covered two systems contracts, namely Build Operate Transfer and Turn Key. Based on the results obtained by analysis of the variable investment feasibility of the NPV, BCR and IRR between the contract system Build Operate Transfer and contract system Turn Key on the interest rate of 9%, 12% and 15%.

Keywords: contract system, financing, internal rate of return, net present value

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16933 Study of Chemical State Analysis of Rubidium Compounds in Lα, Lβ₁, Lβ₃,₄ and Lγ₂,₃ X-Ray Emission Lines with Wavelength Dispersive X-Ray Fluorescence Spectrometer

Authors: Harpreet Singh Kainth

Abstract:

Rubidium salts have been commonly used as an electrolyte to improve the efficiency cycle of Li-ion batteries. In recent years, it has been implemented into the large scale for further technological advances to improve the performance rate and better cyclability in the batteries. X-ray absorption spectroscopy (XAS) is a powerful tool for obtaining the information in the electronic structure which involves the chemical state analysis in the active materials used in the batteries. However, this technique is not well suited for the industrial applications because it needs a synchrotron X-ray source and special sample file for in-situ measurements. In contrast to this, conventional wavelength dispersive X-ray fluorescence (WDXRF) spectrometer is nondestructive technique used to study the chemical shift in all transitions (K, L, M, …) and does not require any special pre-preparation planning. In the present work, the fluorescent Lα, Lβ₁ , Lβ₃,₄ and Lγ₂,₃ X-ray spectra of rubidium in different chemical forms (Rb₂CO₃ , RbCl, RbBr, and RbI) have been measured first time with high resolution wavelength dispersive X-ray fluorescence (WDXRF) spectrometer (Model: S8 TIGER, Bruker, Germany), equipped with an Rh anode X-ray tube (4-kW, 60 kV and 170 mA). In ₃₇Rb compounds, the measured energy shifts are in the range (-0.45 to - 1.71) eV for Lα X-ray peak, (0.02 to 0.21) eV for Lβ₁ , (0.04 to 0.21) eV for Lβ₃ , (0.15 to 0.43) eV for Lβ₄ and (0.22 to 0.75) eV for Lγ₂,₃ X-ray emission lines. The chemical shifts in rubidium compounds have been measured by considering Rb₂CO₃ compounds taking as a standard reference. A Voigt function is used to determine the central peak position of all compounds. Both positive and negative shifts have been observed in L shell emission lines. In Lα X-ray emission lines, all compounds show negative shift while in Lβ₁, Lβ₃,₄, and Lγ₂,₃ X-ray emission lines, all compounds show a positive shift. These positive and negative shifts result increase or decrease in X-ray energy shifts. It looks like that ligands attached with central metal atom attract or repel the electrons towards or away from the parent nucleus. This pulling and pushing character of rubidium affects the central peak position of the compounds which causes a chemical shift. To understand the chemical effect more briefly, factors like electro-negativity, line intensity ratio, effective charge and bond length are responsible for the chemical state analysis in rubidium compounds. The effective charge has been calculated from Suchet and Pauling method while the line intensity ratio has been calculated by calculating the area under the relevant emission peak. In the present work, it has been observed that electro-negativity, effective charge and intensity ratio (Lβ₁/Lα, Lβ₃,₄/Lα and Lγ₂,₃/Lα) are inversely proportional to the chemical shift (RbCl > RbBr > RbI), while bond length has been found directly proportional to the chemical shift (RbI > RbBr > RbCl).

Keywords: chemical shift in L emission lines, bond length, electro-negativity, effective charge, intensity ratio, Rubidium compounds, WDXRF spectrometer

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16932 Numerical Investigations of Unstable Pressure Fluctuations Behavior in a Side Channel Pump

Authors: Desmond Appiah, Fan Zhang, Shouqi Yuan, Wei Xueyuan, Stephen N. Asomani

Abstract:

The side channel pump has distinctive hydraulic performance characteristics over other vane pumps because of its generation of high pressure heads in only one impeller revolution. Hence, there is soaring utilization and application in the fields of petrochemical, food processing fields, automotive and aerospace fuel pumping where high heads are required at low flows. The side channel pump is characterized by unstable flow because after fluid flows into the impeller passage, it moves into the side channel and comes back to the impeller again and then moves to the next circulation. Consequently, the flow leaves the side channel pump following a helical path. However, the pressure fluctuation exhibited in the flow greatly contributes to the unwanted noise and vibration which is associated with the flow. In this paper, a side channel pump prototype was examined thoroughly through numerical calculations based on SST k-ω turbulence model to ascertain the pressure fluctuation behavior. The pressure fluctuation intensity of the 3D unstable flow dynamics were carefully investigated under different working conditions 0.8QBEP, 1.0 QBEP and 1.2QBEP. The results showed that the pressure fluctuation distribution around the pressure side of the blade is greater than the suction side at the impeller and side channel interface (z=0) for all three operating conditions. Part-load condition 0.8QBEP recorded the highest pressure fluctuation distribution because of the high circulation velocity thus causing an intense exchanged flow between the impeller and side channel. Time and frequency domains spectra of the pressure fluctuation patterns in the impeller and the side channel were also analyzed under the best efficiency point value, QBEP using the solution from the numerical calculations. It was observed from the time-domain analysis that the pressure fluctuation characteristics in the impeller flow passage increased steadily until the flow reached the interrupter which separates low-pressure at the inflow from high pressure at the outflow. The pressure fluctuation amplitudes in the frequency domain spectrum at the different monitoring points depicted a gentle decreasing trend of the pressure amplitudes which was common among the operating conditions. The frequency domain also revealed that the main excitation frequencies occurred at 600Hz, 1200Hz, and 1800Hz and continued in the integers of the rotating shaft frequency. Also, the mass flow exchange plots indicated that the side channel pump is characterized with many vortex flows. Operating conditions 0.8QBEP, 1.0 QBEP depicted less and similar vortex flow while 1.2Q recorded many vortex flows around the inflow, middle and outflow regions. The results of the numerical calculations were finally verified experimentally. The performance characteristics curves from the simulated results showed that 0.8QBEP working condition recorded a head increase of 43.03% and efficiency decrease of 6.73% compared to 1.0QBEP. It can be concluded that for industrial applications where the high heads are mostly required, the side channel pump can be designed to operate at part-load conditions. This paper can serve as a source of information in order to optimize a reliable performance and widen the applications of the side channel pumps.

Keywords: exchanged flow, pressure fluctuation, numerical simulation, side channel pump

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16931 Deconvolution of Anomalous Fast Fourier Transform Patterns for Tin Sulfide

Authors: I. Shuro

Abstract:

The crystal structure of Tin Sulfide prepared by certain chemical methods is investigated using High-Resolution Transmission Electron Microscopy (HRTEM), Scanning Electron Microscopy (SEM), and X-ray diffraction (XRD) methods. An anomalous HRTEM Fast Fourier Transform (FFT) exhibited a central scatter of diffraction spots, which is surrounded by secondary clusters of spots arranged in a hexagonal pattern around the central cluster was observed. FFT analysis has revealed a long lattice parameter and mostly viewed along a hexagonal axis where there many columns of atoms slightly displaced from one another. This FFT analysis has revealed that the metal sulfide has a long-range order interwoven chain of atoms in its crystal structure. The observed crystalline structure is inconsistent with commonly observed FFT patterns of chemically synthesized Tin Sulfide nanocrystals and thin films. SEM analysis showed the morphology of a myriad of multi-shaped crystals ranging from hexagonal, cubic, and spherical micro to nanostructured crystals. This study also investigates the presence of quasi-crystals as reflected by the presence of mixed local symmetries.

Keywords: fast fourier transform, high resolution transmission electron microscopy, tin sulfide, crystalline structure

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16930 Experimenting with Error Performance of Systems Employing Pulse Shaping Filters on a Software-Defined-Radio Platform

Authors: Chia-Yu Yao

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This paper presents experimental results on testing the symbol-error-rate (SER) performance of quadrature amplitude modulation (QAM) systems employing symmetric pulse-shaping square-root (SR) filters designed by minimizing the roughness function and by minimizing the peak-to-average power ratio (PAR). The device used in the experiments is the 'bladeRF' software-defined-radio platform. PAR is a well-known measurement, whereas the roughness function is a concept for measuring the jitter-induced interference. The experimental results show that the system employing minimum-roughness pulse-shaping SR filters outperforms the system employing minimum-PAR pulse-shaping SR filters in the sense of SER performance.

Keywords: pulse-shaping filters, FIR filters, jittering, QAM

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16929 A Method for Rapid Evaluation of Ore Breakage Parameters from Core Images

Authors: A. Nguyen, K. Nguyen, J. Jackson, E. Manlapig

Abstract:

With the recent advancement in core imaging systems, a large volume of high resolution drill core images can now be collected rapidly. This paper presents a method for rapid prediction of ore-specific breakage parameters from high resolution mineral classified core images. The aim is to allow for a rapid assessment of the variability in ore hardness within a mineral deposit with reduced amount of physical breakage tests. This method sees its application primarily in project evaluation phase, where proper evaluation of the variability in ore hardness of the orebody normally requires prolong and costly metallurgical test work program. Applying this image-based texture analysis method on mineral classified core images, the ores are classified according to their textural characteristics. A small number of physical tests are performed to produce a dataset used for developing the relationship between texture classes and measured ore hardness. The paper also presents a case study in which this method has been applied on core samples from a copper porphyry deposit to predict the ore-specific breakage A*b parameter, obtained from JKRBT tests.

Keywords: geometallurgy, hyperspectral drill core imaging, process simulation, texture analysis

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16928 Principal Component Analysis in Drug-Excipient Interactions

Authors: Farzad Khajavi

Abstract:

Studies about the interaction between active pharmaceutical ingredients (API) and excipients are so important in the pre-formulation stage of development of all dosage forms. Analytical techniques such as differential scanning calorimetry (DSC), Thermal gravimetry (TG), and Furrier transform infrared spectroscopy (FTIR) are commonly used tools for investigating regarding compatibility and incompatibility of APIs with excipients. Sometimes the interpretation of data obtained from these techniques is difficult because of severe overlapping of API spectrum with excipients in their mixtures. Principal component analysis (PCA) as a powerful factor analytical method is used in these situations to resolve data matrices acquired from these analytical techniques. Binary mixtures of API and interested excipients are considered and produced. Peaks of FTIR, DSC, or TG of pure API and excipient and their mixtures at different mole ratios will construct the rows of the data matrix. By applying PCA on the data matrix, the number of principal components (PCs) is determined so that it contains the total variance of the data matrix. By plotting PCs or factors obtained from the score of the matrix in two-dimensional spaces if the pure API and its mixture with the excipient at the high amount of API and the 1:1mixture form a separate cluster and the other cluster comprise of the pure excipient and its blend with the API at the high amount of excipient. This confirms the existence of compatibility between API and the interested excipient. Otherwise, the incompatibility will overcome a mixture of API and excipient.

Keywords: API, compatibility, DSC, TG, interactions

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16927 Channel Estimation for LTE Downlink

Authors: Rashi Jain

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The LTE systems employ Orthogonal Frequency Division Multiplexing (OFDM) as the multiple access technology for the Downlink channels. For enhanced performance, accurate channel estimation is required. Various algorithms such as Least Squares (LS), Minimum Mean Square Error (MMSE) and Recursive Least Squares (RLS) can be employed for the purpose. The paper proposes channel estimation algorithm based on Kalman Filter for LTE-Downlink system. Using the frequency domain pilots, the initial channel response is obtained using the LS criterion. Then Kalman Filter is employed to track the channel variations in time-domain. To suppress the noise within a symbol, threshold processing is employed. The paper draws comparison between the LS, MMSE, RLS and Kalman filter for channel estimation. The parameters for evaluation are Bit Error Rate (BER), Mean Square Error (MSE) and run-time.

Keywords: LTE, channel estimation, OFDM, RLS, Kalman filter, threshold

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16926 Intercultural Education through Literature Reception: An in-Depth Study of the Cultural and Literary Relations of Romania and China during 1948-2018

Authors: Iulia Elena Gîță

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According to the sociological theory of literature, constraints on the creation and share of cultural works can be placed between two extremes: one with a high level of politicization and the other with a high level of commercialization. The overall objective of the present research is to follow the principles of Sociology of Translation to closely map and analyse the publishing activity of Romania concerning China and Chinese literature during four stages of Romanian history between 1948-2018. This paper proposes, thus, an extended approach to literature, to its cultural, political and economic reception. In achieving the proposed objectives, the research expands far beyond the literary text itself, to its macro context, analysing, through quantitative research methods, a statistical database created based on two phases - the first part containing literary and non-fictional works that address and discuss issues related to China; the second part includes literary translations of Chinese literature into Romanian, either by direct translation or by an intermediate language. Throughout this paper we will map not only the number of works, but also the topics approached by writers along the two periods of the political life of Romania.

Keywords: bilateral relations, Chinese literature, intercultural understanding, international relations, socio-cultural reception, socio-political constraints, publishing

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16925 A Methodology Based on Image Processing and Deep Learning for Automatic Characterization of Graphene Oxide

Authors: Rafael do Amaral Teodoro, Leandro Augusto da Silva

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Originated from graphite, graphene is a two-dimensional (2D) material that promises to revolutionize technology in many different areas, such as energy, telecommunications, civil construction, aviation, textile, and medicine. This is possible because its structure, formed by carbon bonds, provides desirable optical, thermal, and mechanical characteristics that are interesting to multiple areas of the market. Thus, several research and development centers are studying different manufacturing methods and material applications of graphene, which are often compromised by the scarcity of more agile and accurate methodologies to characterize the material – that is to determine its composition, shape, size, and the number of layers and crystals. To engage in this search, this study proposes a computational methodology that applies deep learning to identify graphene oxide crystals in order to characterize samples by crystal sizes. To achieve this, a fully convolutional neural network called U-net has been trained to segment SEM graphene oxide images. The segmentation generated by the U-net is fine-tuned with a standard deviation technique by classes, which allows crystals to be distinguished with different labels through an object delimitation algorithm. As a next step, the characteristics of the position, area, perimeter, and lateral measures of each detected crystal are extracted from the images. This information generates a database with the dimensions of the crystals that compose the samples. Finally, graphs are automatically created showing the frequency distributions by area size and perimeter of the crystals. This methodological process resulted in a high capacity of segmentation of graphene oxide crystals, presenting accuracy and F-score equal to 95% and 94%, respectively, over the test set. Such performance demonstrates a high generalization capacity of the method in crystal segmentation, since its performance considers significant changes in image extraction quality. The measurement of non-overlapping crystals presented an average error of 6% for the different measurement metrics, thus suggesting that the model provides a high-performance measurement for non-overlapping segmentations. For overlapping crystals, however, a limitation of the model was identified. To overcome this limitation, it is important to ensure that the samples to be analyzed are properly prepared. This will minimize crystal overlap in the SEM image acquisition and guarantee a lower error in the measurements without greater efforts for data handling. All in all, the method developed is a time optimizer with a high measurement value, considering that it is capable of measuring hundreds of graphene oxide crystals in seconds, saving weeks of manual work.

Keywords: characterization, graphene oxide, nanomaterials, U-net, deep learning

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16924 Adiabatic Flame Temperature: New Calculation Methode

Authors: Muthana Abdul Mjed Jamel Al-gburi

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The present paper introduces the methane-air flame and its main chemical reaction, the mass burning rate, the burning velocity, and the most important parameter, the adiabatic and its evaluation. Those major important flame parameters will be mathematically formulated and computerized using the MATLAB program. The present program established a new technique to decide the true adiabatic flame temperature. The new technique implements the trial and error procedure to obtained the calculated total internal energy of the product species then evaluate of the reactants ones, from both, we can draw two energy lines their intersection will decide the true required temperature. The obtained results show accurate evaluation for the atmospheric Stoichiometric (Φ=1.05) methane-air flame, and the value was 2136.36 K.

Keywords: 1- methane-air flame, 2-, adiabatic flame temperature, 3-, reaction model, 4- matlab program, 5-, new technique

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16923 An Algorithm of Regulation of Glucose-Insulin Concentration in the Blood

Authors: B. Selma, S. Chouraqui

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The pancreas is an elongated organ that extends across the abdomen, below the stomach. In addition, it secretes certain enzymes that aid in food digestion. The pancreas also manufactures hormones responsible for regulating blood glucose levels. In the present paper, we propose a mathematical model to study the homeostasis of glucose and insulin in healthy human, and a simulation of this model, which depicts the physiological events after a meal, will be represented in ordinary humans. The aim of this paper is to design an algorithm which regulates the level of glucose in the blood. The algorithm applied the concept of expert system for performing an algorithm control in the form of an "active" used to prescribe the rate of insulin infusion. By decomposing the system into subsystems, we have developed parametric models of each subsystem by using a forcing function strategy. The results showed a performance of the control system.

Keywords: modeling, algorithm, regulation, glucose-insulin, blood, control system

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16922 Synthetic Cannabinoids: Extraction, Identification and Purification

Authors: Niki K. Burns, James R. Pearson, Paul G. Stevenson, Xavier A. Conlan

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In Australian state Victoria, synthetic cannabinoids have recently been made illegal under an amendment to the drugs, poisons and controlled substances act 1981. Identification of synthetic cannabinoids in popular brands of ‘incense’ and ‘potpourri’ has been a difficult and challenging task due to the sample complexity and changes observed in the chemical composition of the cannabinoids of interest. This study has developed analytical methodology for the targeted extraction and determination of synthetic cannabinoids available pre-ban. A simple solvent extraction and solid phase extraction methodology was developed that selectively extracted the cannabinoid of interest. High performance liquid chromatography coupled with UV‐visible and chemiluminescence detection (acidic potassium permanganate and tris (2,2‐bipyridine) ruthenium(III)) were used to interrogate the synthetic cannabinoid products. Mass spectrometry and nuclear magnetic resonance spectroscopy were used for structural elucidation of the synthetic cannabinoids. The tris(2,2‐bipyridine)ruthenium(III) detection was found to offer better sensitivity than the permanganate based reagents. In twelve different brands of herbal incense, cannabinoids were extracted and identified including UR‐144, XLR 11, AM2201, 5‐F‐AKB48 and A796‐260.

Keywords: electrospray mass spectrometry, high performance liquid chromatography, solid phase extraction, synthetic cannabinoids

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16921 Phage Therapy as a Potential Solution in the Fight against Antimicrobial Resistance

Authors: Sanjay Shukla

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Excessive use of antibiotics is a main problem in the treatment of wounds and other chronic infections and antibiotic treatment is frequently non-curative, thus alternative treatment is necessary. Phage therapy is considered one of the most effective approaches to treat multi-drug resistant bacterial pathogens. Infections caused by Staphylococcus aureus are very efficiently controlled with phage cocktails, containing a different individual phages lysate infecting a majority of known pathogenic S. aureus strains. The aim of current study was to investigate the efficiency of a purified phage cocktail for prophylactic as well as therapeutic application in mouse model and in large animals with chronic septic infection of wounds. A total of 150 sewage samples were collected from various livestock farms. These samples were subjected for the isolation of bacteriophage by double agar layer method. A total of 27 sewage samples showed plaque formation by producing lytic activity against S. aureus in double agar overlay method out of 150 sewage samples. In TEM recovered isolates of bacteriophages showed hexagonal structure with tail fiber. In the bacteriophage (ØVS) had an icosahedral symmetry with the head size 52.20 nm in diameter and long tail of 109 nm. Head and tail were held together by connector and can be classified as a member of the Myoviridae family under the order of Caudovirale. Recovered bacteriophage had shown the antibacterial activity against the S. aureus in vitro. Cocktail (ØVS1, ØVS5, ØVS9 and ØVS 27) of phage lysate were tested to know in vivo antibacterial activity as well as the safety profile. Result of mice experiment indicated that the bacteriophage lysate was very safe, did not show any appearance of abscess formation which indicates its safety in living system. The mice were also prophylactically protected against S. aureus when administered with cocktail of bacteriophage lysate just before the administration of S. aureus which indicates that they are good prophylactic agent. The S. aureus inoculated mice were completely recovered by bacteriophage administration with 100% recovery which was very good as compere to conventional therapy. In present study ten chronic cases of wound were treated with phage lysate and follow up of these cases was done regularly up to ten days (at 0, 5 and 10 d). Result indicated that the six cases out of ten showed complete recovery of wounds within 10 d. The efficacy of bacteriophage therapy was found to be 60% which was very good as compared to the conventional antibiotic therapy in chronic septic wounds infections. Thus, the application of lytic phage in single dose proved to be innovative and effective therapy for treatment of septic chronic wounds.

Keywords: phage therapy, phage lysate, antimicrobial resistance, S. aureus

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16920 Vaporization of a Single N-Pentane Liquid Drop in a Flowing Immiscible Liquid Media

Authors: Hameed B. Mahood, Ali Sh. Baqir

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Vaporization of a single n-pentane drop in a direct contact with another flowing immiscible liquid (warm water) has been experimentally investigated. The experiments were carried out utilising a cylindrical Perspex tube of diameter 10 cm and height and 150 cm. Saturated liquid n-pentane and warm water at 45oC were used as the dispersed and continuous phases, respectively. Photron FASTCAM SA 1.1high speed camera (75,000f/s) with software V. 321 was implemented during the experiments. Five different continuous phase flow rates (warm water) (10, 20, 30, 40, and 46 L⁄h) were used in the study. The results indicated that the increase of the continuous phase (warm water) flow rate results in increasing of the drop/bubble diameter.

Keywords: drop evaporation, direct contact heat transfer, drop/bubble growth, experimental technique

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16919 Measuring and Evaluating the Effectiveness of Mobile High Efficiency Particulate Air Filtering on Particulate Matter within the Road Traffic Network of a Sample of Non-Sparse and Sparse Urban Environments in the UK

Authors: Richard Maguire

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This research evaluates the efficiency of using mobile HEPA filters to reduce localized Particulate Matter (PM), Total Volatile Organic Chemical (TVOC) and Formaldehyde (HCHO) Air Pollution. The research is being performed using a standard HEPA filter that is tube fitted and attached to a motor vehicle. The velocity of the vehicle is used to generate the pressure difference that allows the filter to remove PM, VOC and HCOC pollution from the localized atmosphere of a road transport traffic route. The testing has been performed on a sample of traffic routes in Non-Sparse and Sparse urban environments within the UK. Pre and Post filter measuring of the PM2.5 Air Quality has been carried out along with demographics of the climate environment, including live filming of the traffic conditions. This provides a base line for future national and international research. The effectiveness measurement is generated through evaluating the difference in PM2.5 Air Quality measured pre- and post- the mobile filter test equipment. A series of further research opportunities and future exploitation options are made based on the results of the research.

Keywords: high efficiency particulate air, HEPA filter, particulate matter, traffic pollution

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16918 Study of Frequency and Distribution of Skin Ionocytes in Caspian Sea Zander Larvae during Acclimation to Different Salinity

Authors: Mohaddeseh Ahmadnezhad, Shahrbano Oryan, Mahmoud Bahmani, Mohammadd Sayad Bourani

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Changes in abundance and size of skin ionocytes were investigated in two larval stage of Caspian sea zander, Sander lucioperca, before and after yolk sac absorption, at 96h after transfer from fresh water (FW; <0.5‰) to 7‰ (estuary) and 12‰ (Caspian sea water=CW) salinity. Survival rate in the stage of after yolk sac absorption were more than larval pre-absorbed yolk sac in condition of salinity (p<0.05). Ionocyte abundance increased significantly in 7 and 12‰ salinity (p<0.05), but not about ionocyte size. The results of this study suggest that development of skin Ionocyte osmoregulatory function and osmoregulation capability of Caspian Sea zander larvae increased with growth of the larvae.

Keywords: Caspian Sea, larvae, Sander lucioperca, salinity, skin ionocyte

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16917 Chemical and Sensory Properties of Chardonnay Wines Produced in Different Oak Barrels

Authors: Valentina Obradović, Josip Mesić, Maja Ergović Ravančić, Kamila Mijowska, Brankica Svitlica

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French oak and American oak barrels are most famous all over the world, but barrels of different origin can also be used for obtaining high quality wines. The aim of this research was to compare the influence of different Slavonian (Croatian) and French oak barrels on the quality of Chardonnay wine. Grapes were grown in Croatian wine growing region of Kutjevo in 2015. Chardonnay wines were tested for basic oenological parameters (alcohol, extract, reducing sugar, SO2, acidity), total polyphenols content (Folin-Ciocalteu method), antioxidant activity (ABTS and DPPH method) and color density. Sensory evaluation was performed by students of viticulture/oenology. Samples produced by classical fermentation and ageing in French oak barrels, had better results for polyphenols and sensory evaluation (especially low toasting level) than samples in Slavonian barrels. All tested samples were scored as a “quality” or “premium quality” wines. Sur lie method of fermentation and ageing in Slavonian oak barrel had very good extraction of polyphenols and high antioxidant activity with the usage of authentic yeasts, while commercial yeast strain resulted in worse chemical and sensory parameters.

Keywords: chardonnay, French oak, Slavonian oak, sur lie

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16916 Morphology Evolution in Titanium Dioxide Nanotubes Arrays Prepared by Electrochemical Anodization

Authors: J. Tirano, H. Zea, C. Luhrs

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Photocatalysis has established as viable option in the development of processes for the treatment of pollutants and clean energy production. This option is based on the ability of semiconductors to generate an electron flow by means of the interaction with solar radiation. Owing to its electronic structure, TiO₂ is the most frequently used semiconductors in photocatalysis, although it has a high recombination of photogenerated charges and low solar energy absorption. An alternative to reduce these limitations is the use of nanostructured morphologies which can be produced during the synthesis of TiO₂ nanotubes (TNTs). Therefore, if possible to produce vertically oriented nanostructures it will be possible to generate a greater contact area with electrolyte and better charge transfer. At present, however, the development of these innovative structures still presents an important challenge for the development of competitive photoelectrochemical devices. This research focuses on established correlations between synthesis variables and 1D nanostructure morphology which has a direct effect on the photocatalytic performance. TNTs with controlled morphology were synthesized by two-step potentiostatic anodization of titanium foil. The anodization was carried out at room temperature in an electrolyte composed of ammonium fluoride, deionized water and ethylene glycol. Consequent thermal annealing of as-prepared TNTs was conducted in the air between 450 °C-550 °C. Morphology and crystalline phase of the TNTs were carried out by SEM, EDS and XRD analysis. As results, the synthesis conditions were established to produce nanostructures with specific morphological characteristics. Anatase was the predominant phase of TNTs after thermal treatment. Nanotubes with 10 μm in length, 40 nm in pore diameter and a surface-volume ratio of 50 are important in photoelectrochemical applications based on TiO₂ due to their 1D characteristics, high surface-volume ratio, reduced radial dimensions and high oxide/electrolyte interface. Finally, this knowledge can be used to improve the photocatalytic activity of TNTs by making additional surface modifications with dopants that improve their efficiency.

Keywords: electrochemical anodization, morphology, self-organized nanotubes, TiO₂ nanotubes

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16915 Predicting the Exposure Level of Airborne Contaminants in Occupational Settings via the Well-Mixed Room Model

Authors: Alireza Fallahfard, Ludwig Vinches, Stephane Halle

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In the workplace, the exposure level of airborne contaminants should be evaluated due to health and safety issues. It can be done by numerical models or experimental measurements, but the numerical approach can be useful when it is challenging to perform experiments. One of the simplest models is the well-mixed room (WMR) model, which has shown its usefulness to predict inhalation exposure in many situations. However, since the WMR is limited to gases and vapors, it cannot be used to predict exposure to aerosols. The main objective is to modify the WMR model to expand its application to exposure scenarios involving aerosols. To reach this objective, the standard WMR model has been modified to consider the deposition of particles by gravitational settling and Brownian and turbulent deposition. Three deposition models were implemented in the model. The time-dependent concentrations of airborne particles predicted by the model were compared to experimental results conducted in a 0.512 m3 chamber. Polystyrene particles of 1, 2, and 3 µm in aerodynamic diameter were generated with a nebulizer under two air changes per hour (ACH). The well-mixed condition and chamber ACH were determined by the tracer gas decay method. The mean friction velocity on the chamber surfaces as one of the input variables for the deposition models was determined by computational fluid dynamics (CFD) simulation. For the experimental procedure, the particles were generated until reaching the steady-state condition (emission period). Then generation stopped, and concentration measurements continued until reaching the background concentration (decay period). The results of the tracer gas decay tests revealed that the ACHs of the chamber were: 1.4 and 3.0, and the well-mixed condition was achieved. The CFD results showed the average mean friction velocity and their standard deviations for the lowest and highest ACH were (8.87 ± 0.36) ×10-2 m/s and (8.88 ± 0.38) ×10-2 m/s, respectively. The numerical results indicated the difference between the predicted deposition rates by the three deposition models was less than 2%. The experimental and numerical aerosol concentrations were compared in the emission period and decay period. In both periods, the prediction accuracy of the modified model improved in comparison with the classic WMR model. However, there is still a difference between the actual value and the predicted value. In the emission period, the modified WMR results closely follow the experimental data. However, the model significantly overestimates the experimental results during the decay period. This finding is mainly due to an underestimation of the deposition rate in the model and uncertainty related to measurement devices and particle size distribution. Comparing the experimental and numerical deposition rates revealed that the actual particle deposition rate is significant, but the deposition mechanisms considered in the model were ten times lower than the experimental value. Thus, particle deposition was significant and will affect the airborne concentration in occupational settings, and it should be considered in the airborne exposure prediction model. The role of other removal mechanisms should be investigated.

Keywords: aerosol, CFD, exposure assessment, occupational settings, well-mixed room model, zonal model

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16914 US Track And Field System: Examining Micro-Level Practices against a Global Model for Integrated Development of Mass and Elite Sport

Authors: Peter Smolianov, Steven Dion, Christopher Schoen, Jaclyn Norberg, Nicholas Stone, Soufiane Rafi

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This study assessed the micro-level elements of track and field development in the US against a model for integrating high-performance sport with mass participation. This investigation is important for the country’s international sport performance, which declined relative to other countries and wellbeing, which in its turn deteriorated as over half of the US population became overweight. A questionnaire was designed for the following elements of the model: talent identification and development as well as advanced athlete support. Survey questions were validated by 12 experts, including academics, executives from sport governing bodies, coaches, and administrators. To determine the areas for improvement, the questionnaires were completed by 102 US track and field coaches representing the country’s regions and coaching levels. Possible advancements were further identified through semi-structured discussions with 10 US track and field administrators. The study found that talent search and development is a critically important area for improvement: 49 percent of respondents had overall negative perceptions, and only 16 percent were positive regarding these US track and field practices. Both quantitative survey results and open responses revealed that the key reason for the inadequate athlete development was a shortage of well-educated and properly paid coaches: 77 percent of respondents indicated that coach expertise is never or rarely high across all participant ages and levels. More than 40 percent of the respondents were uncertain of or not familiar with world’s best talent identification and development practices, particularly methods of introducing children to track and field from outside the sport’s participation base. Millions more could be attracted to the sport by adopting best international practices. First, physical education should be offered a minimum three times a week in all school grades, and track and field together with other healthy sports, should be taught at school to all children. Second, multi-sport events, including track and field disciplines, should be organized for everyone within and among all schools, cities and regions. Three, Australian and Eastern European methods of talent search at schools should be utilized and tailored to the US conditions. Four, comprehensive long term athlete development guidelines should be used for the advancement of the American Development Model, particularly track and field tests and guidelines as part of both school education and high-performance athlete development for every age group from six to over 70 years old. These world’s best practices are to improve the country’s international performance while increasing national sport participation and positively influencing public health.

Keywords: high performance, mass participation, sport development, track and field, USA

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16913 Study of the Behavior of PM₁₀ and SO₂ in the Urban Atmosphere of Sfax: Influence of Anthropised Contributions and Special Meteorological Conditions, 2008

Authors: Allagui Mohamed

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The study of the temporal variation of the PM10 and the SO₂ in the area of Sfax during the year of 2008, showed very significant fluctuations of the contents. They depend on the transmitting sources and the weather conditions. The study of the evolutionary behavior of the PM10 and the SO₂ in a situation of the Sirocco revealed the determining influence of the Sahara which was confirmed by its strong enrichment of the atmosphere with particulate matter. The analysis of a situation of breeze of sea highlighted the increase in the contents of the PM10 of agreement with the increase the speed of the marine wind, in particular for the diurnal period, possibly testifying to the enrichment of the aerosol in a considerable maritime component. A situation of anticyclonic winter examined when with it the accumulation of the contents of the PM10 at a rate of 70 μg/m³ showed such concentrations remained weak by comparison with other studies which show contents of about 300 μg/m³.

Keywords: PM10, sea breeze, SO₂, sirocco, anticyclone

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16912 Hollowfiber Poly Lactid Co-Glycolic Acid (PLGA)-Collagen Coated by Chitosan as a Candidate of Small Diameter Vascular Graft

Authors: Dita Mayasari, Zahrina Mardina, Riki Siswanto, Agresta Ifada, Ova Oktavina, Prihartini Widiyanti

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Heart failure is a serious major health problem with high number of mortality per year. Bypass is one of the solutions that has often been taken. Natural vascular graft (xenograft) as the substitute in bypass is inconvenient due to ethic problems and the risk of infection transmission caused by the usage of another species transgenic vascular. Nowadays, synthetic materials have been fabricated from polymers. The aim of this research is to make a synthetic vascular graft with great physical strength, high biocompatibility, and good affordability. The method of this research was mixing PLGA and collagen by magnetic stirrer. This composite were shaped by spinneret with water as coagulant. Then it was coated by chitosan with 3 variations of weight (1 gram, 2 grams, and 3 grams) to increase hemo and cytocompatibility, proliferation, and cell attachment in order for the vascular graft candidates to be more biocompatible. Mechanical strength for each variation was 5,306 MPa (chitosan 1 gram), 3,433 MPa (chitosan 2 grams) and 3,745 MPa (chitosan 3 grams). All the tensile values were higher than human vascular tensile strength. Toxicity test showed that the living cells in all variations were more than 60% in number, thus the vascular graft is not toxic.

Keywords: chitosan, collagen, PLGA, spinneret

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16911 The Invisibility of Production: A Comparative Study of the Marker of Modern Urban-Centric Economic Development

Authors: Arpita Banerjee

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We now live in a world where half of the human population is city dwellers. The migration of people from rural to urban areas is rising continuously. But, the promise of a greater wage and better quality of life cannot keep up with the pace of migration. The rate of urbanization is much higher in developing countries. The UN predicts that 95 percent of this urban expansion will take place in the developing world in the next few decades. The population in the urban settlements of the developing nations is soaring, and megacities like Mumbai, Dhaka, Jakarta, Karachi, Manila, Shanghai, Rio de Janeiro, Lima, and Kinshasa are crammed with people, a majority of whom are migrants. Rural-urban migration has taken a new shape with the rising number of smaller cities. Apart from the increase in non-agricultural economic activities, growing demand for resources and energy, an increase in wastes and pollution, and a greater ecological footprint, there is another significant characteristic of the current wave of urbanization. This paper analyses that important marker of urbanization. It is the invisibility of production sites. The growing urban space ensures that the producers, the production sites, or the process stay beyond urban visibility. In cities and towns, living is majorly about earning money in either the informal service and small scale manufacturing sectors (a major part of which is food preparation), or the formal service sector. In the cases of both the informal service and small scale manufacturing or the formal service sector, commodity creation cannot be seen. The urban space happens to be the marketplace, where nature and its services, along with the non-urban labour, cannot be seen unless it is sold in the market. Hence, the consumers are now increasingly becoming disengaged from the producers. This paper compares the rate of increase in the size of and employment in the informal sector and/or that of the formal sector of some selected urban areas of India. Also, a comparison over the years of the aforementioned characteristics is presented in this paper, in order to find out how the anonymity of the producers to the urban consumers have grown as urbanization has risen. This paper also analyses the change in the transport cost of goods into the cities and towns of India and supports that claim made here that the invisibility of production is a crucial marker of modern-day urban-centric economic development. Such urbanization has an important ecological impact. The invisibility of the production site saves the urban consumer society from dealing with the ethical and ecological aspects of the production process. Once the real sector production is driven out of the cities and towns, the invisible ethical and ecological impacts of the growing urban consumption frees the consumers from associating themselves with any responsibility towards those impacts.

Keywords: ecological impact of urbanization, informal sector, invisibility of production, urbanization

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