Search results for: maximum distance separable (MDS) matrix
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7890

Search results for: maximum distance separable (MDS) matrix

6090 Comparison of the Postoperative Analgesic Effects of Morphine, Paracetamol, and Ketorolac in Patient-Controlled Analgesia in the Patients Undergoing Open Cholecystectomy

Authors: Siamak Yaghoubi, Vahideh Rashtchi, Marzieh Khezri, Hamid Kayalha, Monadi Hamidfar

Abstract:

Background and objectives: Effective postoperative pain management in abdominal surgeries, which are painful procedures, plays an important role in reducing postoperative complications and increasing patient’s satisfaction. There are many techniques for pain control, one of which is Patient-Controlled Analgesia (PCA). The aim of this study was to compare the analgesic effects of morphine, paracetamol and ketorolac in the patients undergoing open cholecystectomy, using PCA method. Material and Methods: This randomized controlled trial was performed on 330 ASA (American Society of Anesthesiology) I-II patients ( three equal groups, n=110) who were scheduled for elective open cholecystectomy in Shahid Rjaee hospital of Qazvin, Iran from August 2013 until September 2015. All patients were managed by general anesthesia with TIVA (Total Intra Venous Anesthesia) technique. The control group received morphine with maximum dose of 0.02mg/kg/h, the paracetamol group received paracetamol with maximum dose of 1mg/kg/h, and the ketorolac group received ketorolac with maximum daily dose of 60mg using IV-PCA method. The parameters of pain, nausea, hemodynamic variables (BP and HR), pruritus, arterial oxygen desaturation, patient’s satisfaction and pain score were measured every two hours for 8 hours following operation in all groups. Results: There were no significant differences in demographic data between the three groups. there was a statistically significant difference with regard to the mean pain score at all times between morphine and paracetamol, morphine and ketorolac, and paracetamol and ketorolac groups (P<0.001). Results indicated a reduction with time in the mean level of postoperative pain in all three groups. At all times the mean level of pain in ketorolac group was less than that in the other two groups (p<0.001). Conclusion: According to the results of this study ketorolac is more effective than morphine and paracetamol in postoperative pain control in the patients undergoing open cholecystectomy, using PCA method.

Keywords: analgesia, cholecystectomy, ketorolac, morphine, paracetamol

Procedia PDF Downloads 183
6089 Surface Modification of Pineapple Leaf Fibre Reinforced Polylactic Acid Composites

Authors: Januar Parlaungan Siregar, Davindra Brabu Mathivanan, Dandi Bachtiar, Mohd Ruzaimi Mat Rejab, Tezara Cionita

Abstract:

Natural fibres play a significant role in mass industries such as automotive, construction and sports. Many researchers have found that the natural fibres are the best replacement for the synthetic fibres in terms of cost, safety, and degradability due to the shortage of landfill and ingestion of non biodegradable plastic by animals. This study mainly revolved around pineapple leaf fibre (PALF) which is available abundantly in tropical countries and with excellent mechanical properties. The composite formed in this study is highly biodegradable as both fibre and matrix are both derived from natural based products. The matrix which is polylactic acid (PLA) is made from corn starch which gives the upper hand as both material are renewable resources are easier to degrade by bacteria or enzyme. The PALF is treated with different alkaline solution to remove excessive moisture in the fibre to provide better interfacial bonding with PLA. Thereafter the PALF is washed with distilled water several times before placing in vacuum oven at 80°C for 48 hours. The dried PALF later were mixed with PLA using extrusion method using fibre in percentage of 30 by weight. The temperature for all zone were maintained at 160°C with the screw speed of 50 rpm for better bonding and afterwards the products of the mixture were pelletized using pelletizer. The pellets were placed in the specimen-sized mould for hot compression under the temperature of 170°C at 5 MPa for 5 min and subsequently were cold pressed under room temperature at 5 MPa for 5 min. The specimen were tested for tensile and flexure strength according to American Society for Testing and Materials (ASTM) D638 and D790 respectively. The effect of surface modification on PALF with different alkali solution will be investigated and compared.

Keywords: natural fibre, PALF, PLA, composite

Procedia PDF Downloads 283
6088 Genetic Diversity Analysis in Ecological Populations of Persian Walnut

Authors: Masoud Sheidai, Fahimeh Koohdar, Hashem Sharifi

Abstract:

Juglans regia (L.) commonly known as Persian walnut of the genus Juglans L. (Juglandaceae) is one of the most important cultivated plant species due to its high-quality wood and edible nuts. The genetic diversity analysis is essential for conservation and management of tree species. Persian walnut is native from South-Eastern Europe to North-Western China through Tibet, Nepal, Northern India, Pakistan, and Iran. The species like Persian walnut, which has a wide range of geographical distribution, should harbor extensive genetic variability to adapt to environmental fluctuations they face. We aimed to study the population genetic structure of seven Persian walnut populations including three wild and four cultivated populations by using ISSR (Inter simple sequence repeats) and SRAP (Sequence related amplified polymorphism) molecular markers. We also aimed to compare the genetic variability revealed by ISSR neutral multilocus marker and rDNA ITS sequences. The studied populations differed in morphological features as the samples in each population were clustered together and were separate from the other populations. Three wild populations studied were placed close to each other. The mantel test after 5000 times permutation performed between geographical distance and morphological distance in Persian walnut populations produced significant correlation (r = 0.48, P = 0.002). Therefore, as the populations become farther apart, they become more divergent in morphological features. ISSR analysis produced 47 bands/ loci, while we obtained 15 SRAP bands. Gst and other differentiation statistics determined for these loci revealed that most of the ISSR and SRAP loci have very good discrimination power and can differentiate the studied populations. AMOVA performed for these loci produced a significant difference (< 0.05) supporting the above-said result. AMOVA produced significant genetic difference based on ISSR data among the studied populations (PhiPT = 0.52, P = 0.001). AMOVA revealed that 53% of the total variability is due to among population genetic difference, while 47% is due to within population genetic variability. The results showed that both multilocus molecular markers and ITS sequences can differentiate Persian walnut populations. The studied populations differed genetically and showed isolation by distance (IBD). ITS sequence based MP and Bayesian phylogenetic trees revealed that Iranian walnut cultivars form a distinct clade separated from the cultivars studied from elsewhere. Almost all clades obtained have high bootstrap value. The results indicated that a combination of multilpcus and sequencing molecular markers can be used in genetic differentiation of Persian walnut.

Keywords: genetic diversity, population, molecular markers, genetic difference

Procedia PDF Downloads 149
6087 Predictors of Ante-Natal Care and Health Facility Delivery Services Utilization in a Rural Area in Plateau State

Authors: Lilian A. Okeke, I. Okeke, N. Waziri, S. Balogun, P. Nguku, O. Fawole

Abstract:

Background: Access to ante-natal care services promotes safe motherhood and delivery with improved maternal and neonatal outcome. We conducted this study to identify factors influencing the utilization of antenatal care (ANC) and health delivery services. Methods: We conducted a cross sectional study. Households were numbered and a one in three sample was selected using a systematic sampling method. One hundred and ninety eight women who were either pregnant or had previous deliveries were interviewed using pretested structured questionnaires to obtain information on their socio-demographic characteristics, and reasons for non-utilization of ANC and health delivery services. We performed univariate and bivariate analysis using Epi info version 3.5.3. Results: The age of respondents ranged from (17-55 years) with a median age of 29 years. One hundred and ninety two (97%) utilized antenatal care services. Ninety three (47.9%) attended ANC at second trimester. More than half (58.6%) had ≥ 4 visits to ANC. One hundred and thirty one (66.2%) had their last delivery at home by a traditional birth attendant. Factors associated with ANC and health facility delivery services utilization were: age group 45-55 (OR 0.01; 95% CI: 0.00-0.16) and > 55 years (OR 0.03; 95% CI: 0.00-0.60), wife’s educational status (OR 3.17; 95% CI: 1.66-8.30), husband’s permission (OR 11.8; 95% CI 2.19-63.62), and distance ≥ 5km (OR 0.33; 95% CI: 0.16-0.60). Conclusion: ANC services were well utilized. Most women did not book early and had their last delivery at home. Predictors of ANC use and health facility delivery were age, wife’s educational status, husband's permission and long distance from health facility. A one-day health sensitization of the benefits of ANC utilization and the dangers of delivering at home was implemented.

Keywords: ante natal care, health facility, delivery services, rural area, Plateau state

Procedia PDF Downloads 354
6086 Interactions between Residential Mobility, Car Ownership and Commute Mode: The Case for Melbourne

Authors: Solmaz Jahed Shiran, John Hearne, Tayebeh Saghapour

Abstract:

Daily travel behavior is strongly influenced by the location of the places of residence, education, and employment. Hence a change in those locations due to a move or changes in an occupation leads to a change in travel behavior. Given the interventions of housing mobility and travel behaviors, the hypothesis is that a mobile housing market allows households to move as a result of any change in their life course, allowing them to be closer to central services, public transport facilities and workplace and hence reducing the time spent by individuals on daily travel. Conversely, household’s immobility may lead to longer commutes of residents, for example, after a change of a job or a need for new services such as schools for children who have reached their school age. This paper aims to investigate the association between residential mobility and travel behavior. The Victorian Integrated Survey of Travel and Activity (VISTA) data is used for the empirical analysis. Car ownership and journey to work time and distance of employed people are used as indicators of travel behavior. Change of usual residence within the last five years used to identify movers and non-movers. Statistical analysis, including regression models, is used to compare the travel behavior of movers and non-movers. The results show travel time, and the distance does not differ for movers and non-movers. However, this is not the case when taking into account the residence tenure-type. In addition, car ownership rate and number found to be significantly higher for non-movers. It is hoped that the results from this study will contribute to a better understanding of factors other than common socioeconomic and built environment features influencing travel behavior.

Keywords: journey to work, regression models, residential mobility, commute mode, car ownership

Procedia PDF Downloads 117
6085 Study of Climate Change Scenarios (IPCC) in the Littoral Zone of the Caspian Sea

Authors: L. Rashidian, M. Rajabali

Abstract:

Climate changes have unpredictable and costly effects on water resources of various basins. The impact of atmospheric phenomena on human life and the environment is so significant that only knowledge of management can reduce its consequences. In this study, using LARS.WG model and down scaling of general circulation climate model HADCM-3 and according to the IPCC scenarios, including series A1b, A2 and B1, we simulated data from 2010 to 2040 in order to using them for long term forecasting of climate parameters of the Caspian Sea and its impact on sea level. Our research involves collecting data on monthly precipitation amounts, minimum and maximum temperature and daily sunshine hours, from meteorological organization for Caspian Sea coastal station such as Gorgan, Ramsar, Rasht, Anzali, Astara and Ghaemshahr since their establishment until 2010. Considering the fact that the fluctuation range of water level in the Caspian Sea has various ups and downs in different times, there is an increase in minimum and maximum temperature for all the mentioned scenarios, which will last until 2040. Overall, the amount of rainfall in cities bordering the Caspian Sea was studied based on the three scenarios, which shows an increase in the amount. However, there will be a decrease in water level of the Caspian Sea till 2040.

Keywords: IPCC, climate change, atmospheric circulation, Caspian Sea, HADCM3, sea level

Procedia PDF Downloads 224
6084 Cell Adhesion, Morphology and Cytokine Expression of Synoviocytes Can Be Altered on Different Nano-Topographic Oxidized Silicon Nanosponges

Authors: Hung-Chih Hsu, Pey-Jium Chang, Ching-Hsein Chen, Jer-Liang Andrew Yeh

Abstract:

Osteoarthritis (OA) is a common disorder in rehabilitation clinic. The main characteristics include joint pain, localized tenderness and enlargement, joint effusion, cartilage destruction, loss of adhesion of perichondrium, synovium hyperplasia. Synoviocytes inflammation might be a cause of local tenderness and effusion. Inflammation cytokines might also play an important role in joint pain, cartilage destruction, decrease adhesion of perichondrium to the bone. Treatments of osteoarthritis include non-steroid anti-inflammation drugs (NSAID), glucosamine supplementation, hyaluronic acid, arthroscopic debridement, and total joint replacement. Total joint replacement is commonly used in patients with severe OA who failed respond to pharmacological treatment. However, some patients received surgery had serious adverse events, including instability of the implants due to insufficient adhesion to the adjacent bony tissue or synovial inflammation. We tried to develop ideal nano-topographic oxidized silicon nanosponges by using with various chemicals to produce thickness difference in nanometers in order to study more about the cell-environment interactions in vitro like the alterations of cell adhesion, morphology, extracellular matrix secretions in the pathogenesis of osteoarthritis. Cytokines studies like growth factor, reactive oxygen species, reactive inflammatory materials (Like nitrous oxide and prostaglandin E2), extracellular matrix (ECM) degradation enzymes, and synthesis of collagen will also be observed and discussed. Extracellular and intracellular expression transforming growth factor beta (TGF-β) will be studied by reverse transcription-polymerase chain reaction (RT-PCR). The degradation of ECM will be observed by the bioactivity ratio of matrix metalloproteinase (MMP) and tissue inhibitors of metalloproteinase by ELISA (Enzyme-linked immunosorbent assay). When rabbit synoviocytes were cultured on these nano-topographic structures, they demonstrate better cell adhesion rate, decreased expression of MMP-2,9 and PGE2, and increased expression of TGF-β when cultured in nano-topographic oxidized silicon nanosponges than in the planar oxidized silicon ones. These results show cell behavior, cytokine production can be influenced by physical characteristics from different nano-topographic structures. Our study demonstrates the possibility of manipulating cell behavior in these nano-topographic biomaterials.

Keywords: osteoarthritis, synoviocyte, oxidized silicon surfaces, reactive oxygen species

Procedia PDF Downloads 370
6083 Robust Segmentation of Salient Features in Automatic Breast Ultrasound (ABUS) Images

Authors: Lamees Nasser, Yago Diez, Robert Martí, Joan Martí, Ibrahim Sadek

Abstract:

Automated 3D breast ultrasound (ABUS) screening is a novel modality in medical imaging because of its common characteristics shared with other ultrasound modalities in addition to the three orthogonal planes (i.e., axial, sagittal, and coronal) that are useful in analysis of tumors. In the literature, few automatic approaches exist for typical tasks such as segmentation or registration. In this work, we deal with two problems concerning ABUS images: nipple and rib detection. Nipple and ribs are the most visible and salient features in ABUS images. Determining the nipple position plays a key role in some applications for example evaluation of registration results or lesion follow-up. We present a nipple detection algorithm based on color and shape of the nipple, besides an automatic approach to detect the ribs. In point of fact, rib detection is considered as one of the main stages in chest wall segmentation. This approach consists of four steps. First, images are normalized in order to minimize the intensity variability for a given set of regions within the same image or a set of images. Second, the normalized images are smoothed by using anisotropic diffusion filter. Next, the ribs are detected in each slice by analyzing the eigenvalues of the 3D Hessian matrix. Finally, a breast mask and a probability map of regions detected as ribs are used to remove false positives (FP). Qualitative and quantitative evaluation obtained from a total of 22 cases is performed. For all cases, the average and standard deviation of the root mean square error (RMSE) between manually annotated points placed on the rib surface and detected points on rib borders are 15.1188 mm and 14.7184 mm respectively.

Keywords: Automated 3D Breast Ultrasound, Eigenvalues of Hessian matrix, Nipple detection, Rib detection

Procedia PDF Downloads 319
6082 Effectiveness of Column Geometry in High-Rise Buildings

Authors: Man Singh Meena

Abstract:

Structural engineers are facing different kind of challenges due to innovative & bold ideas of architects who are trying to design every structure with uniqueness. In RCC frame structures different geometry of columns can be used in design and rectangular columns can be placed with different type orientation. The analysis is design of structures can also be carried out by different type of software available i.e., STAAD Pro, ETABS and TEKLA. In recent times high-rise building modeling & analysis is done by ETABS due to its certain features which are superior to other software. The case study in this paper mainly emphasizes on structural behavior of high rise building for different column shape configurations like Circular, Square, Rectangular and Rectangular with 90-degree Rotation and rectangular shape plan. In all these column shapes the areas of columns are kept same to study the effect on design of concrete area is same. Modelling of 20-storeys R.C.C. framed building is done on the ETABS software for analysis. Post analysis of the structure, maximum bending moments, shear forces and maximum longitudinal reinforcement are computed and compared for three different story structures to identify the effectiveness of geometry of column.

Keywords: high-rise building, column geometry, building modelling, ETABS analysis, building design, structural analysis, structural optimization

Procedia PDF Downloads 56
6081 Age and Population Structure of the Goby Parapocryptes Serperaster in the Mekong Delta, Vietnam, Based on Length-Frequency and Otolith Analyses

Authors: Quang Minh Dinh, Jian Guang Qin, Sabine Dittmann, Dinh Dac Tran

Abstract:

The age and population structure the dermal gopy Parapocryptes serperaster were studied using length distributions, otolith and von Bertalanffy model in the Mekong Delta over a whole year through monthly sampling. The sex ratio of P. serperaster was near 1:1, and von Bertalanffy growth parameters were L∞= 25.2 cm, K = 0.74 yr-1, and t0 = -0.22 yr-1. Fish size at first entry to fishery was 14.6 cm, and fishing mortality (1.57 yr-1) and natural mortality (1.51 yr-1) accounted for 51% and 49% of the total mortality (3.07 yr-1), respectively. Relative yield-per-recruit and biomass-per-recruit analyses revealed the levels of maximum exploitation yield (Emax = 0.83), maximum economic yield (E0.1 = 0.71) and the yield at 50% reduction of exploitation (E0.5 = 0.37). Otoliths from 164 female and 196 male gobies were readable, and the otolith morphometry data were used for age identification. The mean age estimated by reading otolith annual rings and by analysing length frequency distribution was consistent. This study shows that the otolith morphometry is a reliable method for aging this goby and possibly also applicable for other tropical gobies. The fishery analysis indicates that this goby stock has not been overexploited in the Mekong Delta.

Keywords: Parapcryptes serperaster, otolith, age, pulation structure, Vietnam

Procedia PDF Downloads 635
6080 Maximum Deformation Estimation for Reinforced Concrete Buildings Using Equivalent Linearization Method

Authors: Chien-Kuo Chiu

Abstract:

In the displacement-based seismic design and evaluation, equivalent linearization method is one of the approximation methods to estimate the maximum inelastic displacement response of a system. In this study, the accuracy of two equivalent linearization methods are investigated. The investigation consists of three soil condition in Taiwan (Taipei Basin 1, 2, and 3) and five different heights of building (H_r= 10, 20, 30, 40, and 50 m). The first method is the Taiwan equivalent linearization method (TELM) which was proposed based on Japanese equivalent linear method considering the modification factor, α_T= 0.85. On the basis of Lin and Miranda study, the second method is proposed with some modification considering Taiwan soil conditions. From this study, it is shown that Taiwanese equivalent linearization method gives better estimation compared to the modified Lin and Miranda method (MLM). The error index for the Taiwanese equivalent linearization method are 16%, 13%, and 12% for Taipei Basin 1, 2, and 3, respectively. Furthermore, a ductility demand spectrum of single-degree-of-freedom (SDOF) system is presented in this study as a guide for engineers to estimate the ductility demand of a structure.

Keywords: displacement-based design, ductility demand spectrum, equivalent linearization method, RC buildings, single-degree-of-freedom

Procedia PDF Downloads 150
6079 Impact of COVID-19 Pandemic on Iraqi Students’ Educational and Psychological Status

Authors: Bahman Gorjian

Abstract:

The notorious COVID-19 is known as an illness that is caused by a novel coronavirus. Since its breakthrough, most governments have decided to temporarily close educational institutions in an attempt to reduce the spread of this disease. Distance education in Iran, like other countries, started from the beginning of the pandemic and caused the closure of schools and universities as an immediate response to control the spread of the virus. The present study followed two aims: First, to investigate if Iraqi M.A students majoring in TEFL who have been studying in Iranian universities during the pandemic believe that COVID-19 had negative/positive effects on their educational achievement; and second, to find how frequently these Iraqi M.A students have experienced psychological problems (e.g., anxiety, numbness, nightmares, nervousness) during the COVID-19. The participants were both male and female students who were admitted for M.A. TEFL courses at 4 Iranian Universities (Abadan Brach, Ahvaz Branch, Science and Research Branch, and Shiraz Branch of Islamic Azad University) for the winter academic term of 2020. The start of their classes coincided with the global outbreak of COVID-19. They were invited to take part in the present study through snowball sampling and were asked to provide their views on two questionnaires. The instruments used for gathering the data were the educational achievement questionnaire and self-rating anxiety scale. The results of the analysis suggested that the participants believed in the negative effects of COVID-19 on their education; the results also suggested COVID-19 affected participants’ psychological states. The discussed findings may have implications for international students and experts interested in the online education system.

Keywords: COVID-19, distance education, Iraqi M.A. students, teaching English as a foreign language, educational impacts, psychological impacts

Procedia PDF Downloads 65
6078 Potential Usefulness of Video Lectures as a Tool to Improve Synchronous and Asynchronous the Online Education

Authors: Omer Shujat Bhatti, Afshan Huma

Abstract:

Online educational system were considered a great opportunity for distance learning. In recent days of COVID19 pandemic, it enable the continuation of educational activities at all levels of education, from primary school to the top level universities. One of the key considered element in supporting the online educational system is video lectures. The current research explored the usefulness of the video lectures delivered to technical students of masters level with a focus on MSc Sustainable Environmental design students who have diverse backgrounds in the formal educational system. Hence they were unable to cope right away with the online system and faced communication and understanding issues in the lecture session due to internet and allied connectivity issues. Researcher used self prepared video lectures for respective subjects and provided them to the students using Youtube channel and subject based Whatsapp groups. Later, students were asked about the usefulness of the lectures towards a better understanding of the subject and an overall enhanced learning experience. More than 80% of the students appreciated the effort and requested it to be part of the overall system. Data collection was done using an online questionnaire which was prior briefed to the students with the purpose of research. It was concluded that video lectures should be considered an integral part of the lecture sessions and must be provided prior to the lecture session, ensuring a better quality of delivery. It was also recommended that the existing system must be upgraded to support the availability of these video lectures through the portal. Teachers training must be provided to help develop quality video content ensuring that is able to cover the content and courses taught.

Keywords: video lectures, online distance education, synchronous instruction, asynchronous communication

Procedia PDF Downloads 99
6077 A Strategy to Oil Production Placement Zones Based on Maximum Closeness

Authors: Waldir Roque, Gustavo Oliveira, Moises Santos, Tatiana Simoes

Abstract:

Increasing the oil recovery factor of an oil reservoir has been a concern of the oil industry. Usually, the production placement zones are defined after some analysis of geological and petrophysical parameters, being the rock porosity, permeability and oil saturation of fundamental importance. In this context, the determination of hydraulic flow units (HFUs) renders an important step in the process of reservoir characterization since it may provide specific regions in the reservoir with similar petrophysical and fluid flow properties and, in particular, techniques supporting the placement of production zones that favour the tracing of directional wells. A HFU is defined as a representative volume of a total reservoir rock in which petrophysical and fluid flow properties are internally consistent and predictably distinct of other reservoir rocks. Technically, a HFU is characterized as a rock region that exhibit flow zone indicator (FZI) points lying on a straight line of the unit slope. The goal of this paper is to provide a trustful indication for oil production placement zones for the best-fit HFUs. The FZI cloud of points can be obtained from the reservoir quality index (RQI), a function of effective porosity and permeability. Considering log and core data the HFUs are identified and using the discrete rock type (DRT) classification, a set of connected cell clusters can be found and by means a graph centrality metric, the maximum closeness (MaxC) cell is obtained for each cluster. Considering the MaxC cells as production zones, an extensive analysis, based on several oil recovery factor and oil cumulative production simulations were done for the SPE Model 2 and the UNISIM-I-D synthetic fields, where the later was build up from public data available from the actual Namorado Field, Campos Basin, in Brazil. The results have shown that the MaxC is actually technically feasible and very reliable as high performance production placement zones.

Keywords: hydraulic flow unit, maximum closeness centrality, oil production simulation, production placement zone

Procedia PDF Downloads 308
6076 Water Productivity as an Indicator of Bioenergetic Sustainability in Sugarcane

Authors: Rubens Duarte Coelho, Timóteo Herculino da Silva Barros, Jefferson de Olveira Costa

Abstract:

Brazil has an electrical matrix of predominantly renewable origin, with emphasis on water sources, which account for 65.2%, biomass energy for 8.2%, wind for 6.8% and solar for 0.13% of the domestic supply. Among these sources, sugarcane cultivation stands out, aiming both at the production of bioethanol and biomass to supply “clean energy”. However, like all other crops, sugar cane demands a large volume of a natural resource that is increasingly “scarce” in quantity and quality: water. Adequate and strategic water management throughout the entire sugarcane cycle is of fundamental importance, and water productivity can be used to adjust irrigation planning and decision-making, increasing the productivity of stalks, bioethanol, biomass, and sugar. In this way, water productivity is a good indicator for analysis and decision-making considering the sustainability of cultivation, as it allows evaluation of the variation in the ratio between production and the amount of water used, suggesting values that maximize the use of this natural resource. In this context, studies that relate water demand, in this case, expressed by water productivity, with the energy production of this crop, in this case, expressed by the production of bioethanol, biomass and sugar, are fundamental to obtaining an efficient production of renewable energy, which aims at the rational use of natural resources, especially water. The objective of the present work was to evaluate the response of sugarcane varieties subjected to different water availability to obtain better sustainability in bioenergy production, presenting water productivity indices for Bioethanol, Sugar and Biomass. The variety that responded best was RB966928, with a bioethanol yield of 68.7 L Mg-1. Future research should focus on the water response under each of the sugarcane fractions in terms of their elemental composition so that the influence of water on the energy supply of this crop can be better understood.

Keywords: energy matrix, water use, water use efficiency, sustainability

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6075 Numerical Studies for Standard Bi-Conjugate Gradient Stabilized Method and the Parallel Variants for Solving Linear Equations

Authors: Kuniyoshi Abe

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Bi-conjugate gradient (Bi-CG) is a well-known method for solving linear equations Ax = b, for x, where A is a given n-by-n matrix, and b is a given n-vector. Typically, the dimension of the linear equation is high and the matrix is sparse. A number of hybrid Bi-CG methods such as conjugate gradient squared (CGS), Bi-CG stabilized (Bi-CGSTAB), BiCGStab2, and BiCGstab(l) have been developed to improve the convergence of Bi-CG. Bi-CGSTAB has been most often used for efficiently solving the linear equation, but we have seen the convergence behavior with a long stagnation phase. In such cases, it is important to have Bi-CG coefficients that are as accurate as possible, and the stabilization strategy, which stabilizes the computation of the Bi-CG coefficients, has been proposed. It may avoid stagnation and lead to faster computation. Motivated by a large number of processors in present petascale high-performance computing hardware, the scalability of Krylov subspace methods on parallel computers has recently become increasingly prominent. The main bottleneck for efficient parallelization is the inner products which require a global reduction. The resulting global synchronization phases cause communication overhead on parallel computers. The parallel variants of Krylov subspace methods reducing the number of global communication phases and hiding the communication latency have been proposed. However, the numerical stability, specifically, the convergence speed of the parallel variants of Bi-CGSTAB may become worse than that of the standard Bi-CGSTAB. In this paper, therefore, we compare the convergence speed between the standard Bi-CGSTAB and the parallel variants by numerical experiments and show that the convergence speed of the standard Bi-CGSTAB is faster than the parallel variants. Moreover, we propose the stabilization strategy for the parallel variants.

Keywords: bi-conjugate gradient stabilized method, convergence speed, Krylov subspace methods, linear equations, parallel variant

Procedia PDF Downloads 148
6074 Ultrasound-Assisted Sol – Gel Synthesis of Nano-Boehmite for Biomedical Purposes

Authors: Olga Shapovalova, Vladimir Vinogradov

Abstract:

Among many different sol – gel matrices only alumina can be successfully parenteral injected in the human body. And this is not surprising, because boehmite (aluminium oxyhydroxide) is the metal oxide approved by FDA and EMA for intravenous and intramuscular administrations, and also has been using for a longtime as adjuvant for producing of many modern vaccines. In our earlier study, it has been shown, that denaturation temperature of enzymes entrapped in sol-gel boehmite matrix increases for 30 – 60 °С with preserving of initial activity. It makes such matrices more attractive for long-term storage of non-stable drugs. In current work we present ultrasound-assisted sol-gel synthesis of nano-boehmite. This method provides bio-friendly, very stable, highly homogeneous alumina sol with using only water and aluminium isopropoxide as a precursor. Many parameters of the synthesis were studied in details: time of ultrasound treatment, US frequency, surface area, pore and nanoparticle size, zeta potential and others. Here we investigated the dependence of stability of colloidal sols and textural properties of the final composites as a function of the time of ultrasonic treatment. Chosen ultrasonic treatment time was between 30 and 180 minutes. Surface area, average pore diameter and total pore volume of the final composites were measured by surface and pore size analyzer Nova 1200 Quntachrome. It was shown that the matrices with ultrasonic treatment time equal to 90 minutes have the biggest surface area 431 ± 24 m2/g. On the other had such matrices have a smaller stability in comparison with the samples with ultrasonic treatment time equal to 120 minutes that have the surface area 390 ± 21 m2/g. It was shown that the stable sols could be formed only after 120 minutes of ultrasonic treatment, otherwise the white precipitate of boehmite is formed. We conclude that the optimal ultrasonic treatment time is 120 minutes.

Keywords: boehmite matrix, stabilisation, ultrasound-assisted sol-gel synthesis

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6073 Paleobathymetry and Biostratigraphy of Sambipitu Formation and Its Relation with the Presence of Ichnofossil in Geoheritage Site Ngalang River Yogyakarta

Authors: Harman Dwi R., Alwin Mugiyantoro, Heppy Chintya P.

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The location of this research is a part of Geoheritage that located in Nglipar, Gunung Kidul Regency, Yogyakarta Special Region. Whereas in this location, the carbonate sandstone of Sambipitu Formation (early-middle Miocene) is well exposed along Ngalang River, also there are ichnofossil presence which causes this formation to be interesting. The determination of paleobathymetry is particularly important in determining paleoenvironment and paleogeographic. Paleobathymetry can be determined by identifying the presence of Foraminifera bentonik fossil and parasequence emerge. The methods that used in this study are spatial method of field observation with systematic sampling, descriptive method of paleontology, biostratigraphy analysis, geometrical analysis of Ichnofossil, and study literature. The result obtained that paleobathymetry of this location is bathyal zone with maximum regression known by Bulliminoides williamsonianus showing depth 17 fathoms at the age of N3-N5 (Oligocenne-Early Miocene) and the maximum transgression is known by Cibicides pseudoungarianus showing depth 862 fathoms at the age of N8-N9 (Early-Middle Miocene). Where the obtained paleobathymetry supported of the presence and formed the pattern of ichnofossil that found in the study area.

Keywords: paleobathymetry, biostratigraphy, ichnofossil, Ngalang river

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6072 Lithium and Sodium Ion Capacitors with High Energy and Power Densities based on Carbons from Recycled Olive Pits

Authors: Jon Ajuria, Edurne Redondo, Roman Mysyk, Eider Goikolea

Abstract:

Hybrid capacitor configurations are now of increasing interest to overcome the current energy limitations of supercapacitors entirely based on non-Faradaic charge storage. Among them, Li-ion capacitors including a negative battery-type lithium intercalation electrode and a positive capacitor-type electrode have achieved tremendous progress and have gone up to commercialization. Inexpensive electrode materials from renewable sources have recently received increased attention since cost is a persistently major criterion to make supercapacitors a more viable energy solution, with electrode materials being a major contributor to supercapacitor cost. Additionally, Na-ion battery chemistries are currently under development as less expensive and accessible alternative to Li-ion based battery electrodes. In this work, we are presenting both lithium and sodium ion capacitor (LIC & NIC) entirely based on electrodes prepared from carbon materials derived from recycled olive pits. Yearly, around 1 million ton of olive pit waste is generated worldwide, of which a third originates in the Spanish olive oil industry. On the one hand, olive pits were pyrolized at different temperatures to obtain a low specific surface area semigraphitic hard carbon to be used as the Li/Na ion intercalation (battery-type) negative electrode. The best hard carbon delivers a total capacity of 270mAh/g vs Na/Na+ in 1M NaPF6 and 350mAh/g vs Li/Li+ in 1M LiPF6. On the other hand, the same hard carbon is chemically activated with KOH to obtain high specific surface area -about 2000 m2g-1- activated carbon that is further used as the ion-adsorption (capacitor-type) positive electrode. In a voltage window of 1.5-4.2V, activated carbon delivers a specific capacity of 80 mAh/g vs. Na/Na+ and 95 mAh/g vs. Li/Li+ at 0.1A /g. Both electrodes were assembled in the same hybrid cell to build a LIC/NIC. For comparison purposes, a symmetric EDLC supercapacitor cell using the same activated carbon in 1.5M Et4NBF4 electrolyte was also built. Both LIC & NIC demonstrates considerable improvements in the energy density over its EDLC counterpart, delivering a maximum energy density of 110Wh/Kg at a power density of 30W/kg AM and a maximum power density of 6200W/Kg at an energy density of 27 Wh/Kg in the case of NIC and a maximum energy density of 110Wh/Kg at a power density of 30W/kg and a maximum power density of 18000W/Kg at an energy density of 22 Wh/Kg in the case of LIC. In conclusion, our work demonstrates that the same biomass waste can be adapted to offer a hybrid capacitor/battery storage device overcoming the limited energy density of corresponding double layer capacitors.

Keywords: hybrid supercapacitor, Na-Ion capacitor, supercapacitor, Li-Ion capacitor, EDLC

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6071 Heat Transfer and Diffusion Modelling

Authors: R. Whalley

Abstract:

The heat transfer modelling for a diffusion process will be considered. Difficulties in computing the time-distance dynamics of the representation will be addressed. Incomplete and irrational Laplace function will be identified as the computational issue. Alternative approaches to the response evaluation process will be provided. An illustration application problem will be presented. Graphical results confirming the theoretical procedures employed will be provided.

Keywords: heat, transfer, diffusion, modelling, computation

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6070 Analysis of the Influence of Fiber Volume and Fiber Orientation on Post-Cracking Behavior of Steel Fiber Reinforced Concrete

Authors: Marilia M. Camargo, Luisa A. Gachet-Barbosa, Rosa C. C. Lintz

Abstract:

The addition of fibers into concrete matrix can enhance some properties of the composite, such as tensile, flexural and impact strengths, toughness, deformation capacity and post-cracking ductility. Many factors affect the mechanical behavior of fiber reinforced concrete, such as concrete matrix (concrete strength, additions, aggregate diameter, etc.), characteristics of the fiber (geometry, type, aspect ratio, volume, orientation, distribution, strength, stiffness, etc.), specimen (size, geometry, method of preparation and loading rate). This research investigates the effects of fiber volume and orientation on the post-cracking behavior of steel fiber reinforced concrete (SFRC). Hooked-end steel fibers with aspect ratios of 45 were added into concrete with volume of 0,32%, 0,64%, 0,94%. The post-cracking behaviour was assessed by double punch test of cubic specimens and the actual volume and orientation of the fibers were determined by non-destructive tests by means of electromagnetic induction. The results showed that the actual volume of fibers in each sample differs in a small amount from the dosed volume of fibers and that the deformation and toughness of the concrete increase with the increase in the actual volume of fibers. In determining the orientation of the fibers, it was found that they tend to distribute more in the X and Y axes due to the influence of the walls of the mold. In addition, it was concluded that the orientation of the fibers is important in the post-cracking behaviour of FRC when analyzed together with the actual volume of fibers, since the greater the volume of fibers, the greater the number of fibers oriented orthogonally to the application of loadings and, consequently, there is a better mechanical behavior of the composite. These results provide a better understanding of the influence of volume and fiber orientation on the post-cracking behavior of the FRC.

Keywords: fiber reinforced concrete, steel fibers, volume of fibers, orientation of fibers, post-cracking behaviour

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6069 A Handheld Light Meter Device for Methamphetamine Detection in Oral Fluid

Authors: Anindita Sen

Abstract:

Oral fluid is a promising diagnostic matrix for drugs of abuse compared to urine and serum. Detection of methamphetamine in oral fluid would pave way for the easy evaluation of impairment in drivers during roadside drug testing as well as ensure safe working environments by facilitating evaluation of impairment in employees at workplaces. A membrane-based point-of-care (POC) friendly pre-treatment technique has been developed which aided elimination of interferences caused by salivary proteins and facilitated the demonstration of methamphetamine detection in saliva using a gold nanoparticle based colorimetric aptasensor platform. It was found that the colorimetric response in saliva was always suppressed owing to the matrix effects. By navigating the challenging interfering issues in saliva, we were successfully able to detect methamphetamine at nanomolar levels in saliva offering immense promise for the translation of these platforms for on-site diagnostic systems. This subsequently motivated the development of a handheld portable light meter device that can reliably transduce the aptasensors colorimetric response into absorbance, facilitating quantitative detection of analyte concentrations on-site. This is crucial due to the prevalent unreliability and sensitivity problems of the conventional drug testing kits. The fabricated light meter device response was validated against a standard UV-Vis spectrometer to confirm reliability. The portable and cost-effective handheld detector device features sensitivity comparable to the well-established UV-Vis benchtop instrument and the easy-to-use device could potentially serve as a prototype for a commercial device in the future.

Keywords: aptasensors, colorimetric gold nanoparticle assay, point-of-care, oral fluid

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6068 Audit on the Use of T-MACS Decision Aid for Patients Presenting to ED with Chest Pain

Authors: Saurav Dhawan, Sanchit Bansal

Abstract:

Background T-MACS is a computer-based decision aid that ‘rules in’ and ‘rules out’ ACS using a combination of the presence or absence of six clinical features with only one biomarker measured on arrival: hs-cTnT. T-MACS had 99.3% negative predictive value and 98.7% sensitivity for ACS, ‘ruling out’ ACS in 40% of patients while ‘ruling in’ 5% at the highest risk. We aim at benchmarking the use of T-MACS which could help to conserve healthcare resources, facilitate early discharges, and ensure safe practice. Methodology Randomized retrospective data collection (n=300) was done from ED electronic records across 3 hospital sites within MFT over a period of 2 months. Data was analysed and compared by percentage for the usage of T-MACS, number of admissions/discharges, and in days for length of stay in hospital. Results MRI A&E had the maximum compliance with the use of T-MACS in the trust at 66%, with minimum admissions (44%) and an average length of stay of 1.825 days. NMG A&E had an extremely low compliance rate (8 %), with 75% admission and 3.387 days as the average length of stay. WYT A&E had no TMACS recorded, with a maximum of 79% admissions and the longest average length of stay at 5.07 days. Conclusion All three hospital sites had a RAG rating of ‘RED’ as per the compliance levels. The assurance level was calculated as ‘Very Limited’ across all sites. There was a positive correlation observed between compliance with TMACS and direct discharges from ED, thereby reducing the average length of stay for patients in the hospital.

Keywords: ACS, discharges, ED, T-MACS

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6067 Study of Bifurcation Curve with Aspect Ratio at Low Reynolds Number

Authors: Amit K. Singh, Subhankar Sen

Abstract:

The bifurcation curve of separation in steady two-dimensional viscous flow past an elliptic cylinder is studied by varying the angle of incidence (α) with different aspect ratio (ratio of minor to major axis). The solutions are based on numerical investigation, using finite element analysis, of the Navier-Stokes equations for incompressible flow. Results are presented for Reynolds number up to 50 and angle of incidence varies from 0° to 90°. Range of aspect ratio (Ar) is from 0.1 to 1 (in steps of 0.1) and flow is considered as unbounded flow. Bifurcation curve represents the locus of Reynolds numbers (Res) at which flow detaches or separates from the surface of the body at a given α and Ar. In earlier studies, effect of Ar on laminar separation curve or bifurcation curve is limited for Ar = 0.1, 0.2, 0.5 and 0.8. Some results are also available at α = 90° and 45°. The present study attempts to provide a systematic data and clear understanding on the effect of Ar at bifurcation curve and its point of maxima. In addition, issues regarding location of separation angle and maximum ratio of coefficient of lift to drag are studied. We found that nature of curve, separation angle and maximum ratio of lift to drag changes considerably with respect to change in Ar.

Keywords: aspect ratio, bifurcation curve, elliptic cylinder, GMRES, stabilized finite-element

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6066 Heat Stress Adaptive Urban Design Intervention for Planned Residential Areas of Khulna City: Case Study of Sonadanga

Authors: Tanjil Sowgat, Shamim Kobir

Abstract:

World is now experiencing the consequences of climate change such as increased heat stress due to high temperature rise. In the context of changing climate, this study intends to find out the planning interventions necessary to adapt to the current heat stress in the planned residential areas of Khulna city. To carry out the study Sonadanga residential area (phase I) of Khulna city has been taken as the study site. This residential neighbourhood covering an area of 30 acres has 206 residential plots. The study area comprises twelve access roads, one park, one playfield, one water body and two street furniture’s. This study conducts visual analysis covering green, open space, water body, footpath, drainage and street trees and furniture and questionnaire survey deals with socio-economic, housing tenancy, experience of heat stress and urban design interventions. It finds that the current state that accelerates the heat stress condition such as lack of street trees and inadequate shading, maximum uses are not within ten minutes walking distance, no footpath for the pedestrians and lack of well-maintained street furniture. It proposes that to adapt to the heat stress pedestrian facilities, buffer sidewalk with landscaping, street trees and open spaces, soft scape, natural and man-made water bodies, green roofing could be effective urban design interventions. There are evidences of limited number of heat stress adaptive planned residential area. Since current sub-division planning practice focuses on rigid land use allocation, it partly addresses the climatic concerns through creating open space and street trees. To better respond to adapt to the heat stress, urban design considerations in the context of sub-division practice would bring more benefits.

Keywords: climate change, urban design, adaptation, heat stress, water-logging

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6065 A Peg Board with Photo-Reflectors to Detect Peg Insertion and Pull-Out Moments

Authors: Hiroshi Kinoshita, Yasuto Nakanishi, Ryuhei Okuno, Toshio Higashi

Abstract:

Various kinds of pegboards have been developed and used widely in research and clinics of rehabilitation for evaluation and training of patient’s hand function. A common measure in these peg boards is a total time of performance execution assessed by a tester’s stopwatch. Introduction of electrical and automatic measurement technology to the apparatus, on the other hand, has been delayed. The present work introduces the development of a pegboard with an electric sensor to detect moments of individual peg’s insertion and removal. The work also gives fundamental data obtained from a group of healthy young individuals who performed peg transfer tasks using the pegboard developed. Through trails and errors in pilot tests, two 10-hole peg-board boxes installed with a small photo-reflector and a DC amplifier at the bottom of each hole were designed and built by the present authors. The amplified electric analogue signals from the 20 reflectors were automatically digitized at 500 Hz per channel, and stored in a PC. The boxes were set on a test table at different distances (25, 50, 75, and 125 mm) in parallel to examine the effect of hole-to-hole distance. Fifty healthy young volunteers (25 in each gender) as subjects of the study performed successive fast 80 time peg transfers at each distance using their dominant and non-dominant hands. The data gathered showed a clear-cut light interruption/continuation moment by the pegs, allowing accurately (no tester’s error involved) and precisely (an order of milliseconds) to determine the pull out and insertion times of each peg. This further permitted computation of individual peg movement duration (PMD: from peg-lift-off to insertion) apart from hand reaching duration (HRD: from peg insertion to lift-off). An accidental drop of a peg led to an exceptionally long ( < mean + 3 SD) PMD, which was readily detected from an examination of data distribution. The PMD data were commonly right-skewed, suggesting that the median can be a better estimate of individual PMD than the mean. Repeated measures ANOVA using the median values revealed significant hole-to-hole distance, and hand dominance effects, suggesting that these need to be fixed in the accurate evaluation of PMD. The gender effect was non-significant. Performance consistency was also evaluated by the use of quartile variation coefficient values, which revealed no gender, hole-to-hole, and hand dominance effects. The measurement reliability was further examined using interclass correlation obtained from 14 subjects who performed the 25 and 125 mm hole distance tasks at two 7-10 days separate test sessions. Inter-class correlation values between the two tests showed fair reliability for PMD (0.65-0.75), and for HRD (0.77-0.94). We concluded that a sensor peg board developed in the present study could provide accurate (excluding tester’s errors), and precise (at a millisecond rate) time information of peg movement separated from that used for hand movement. It could also easily detect and automatically exclude erroneous execution data from his/her standard data. These would lead to a better evaluation of hand dexterity function compared to the widely used conventional used peg boards.

Keywords: hand, dexterity test, peg movement time, performance consistency

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6064 Sustainable Hydrogel Nanocomposites Based on Grafted Chitosan and Clay for Effective Adsorption of Cationic Dye

Authors: H. Ferfera-Harrar, T. Benhalima, D. Lerari

Abstract:

Contamination of water, due to the discharge of untreated industrial wastewaters into the ecosystem, has become a serious problem for many countries. In this study, bioadsorbents based on chitosan-g-poly(acrylamide) and montmorillonite (MMt) clay (CTS-g-PAAm/MMt) hydrogel nanocomposites were prepared via free‐radical grafting copolymerization and crosslinking of acrylamide monomer (AAm) onto natural polysaccharide chitosan (CTS) as backbone, in presence of various contents of MMt clay as nanofiller. Then, they were hydrolyzed to obtain highly functionalized pH‐sensitive nanomaterials with uppermost swelling properties. Their structure characterization was conducted by X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) analyses. The adsorption performances of the developed nanohybrids were examined for removal of methylene blue (MB) cationic dye from aqueous solutions. The factors affecting the removal of MB, such as clay content, pH medium, adsorbent dose, initial dye concentration and temperature were explored. The adsorption process was found to be highly pH dependent. From adsorption kinetic results, the prepared adsorbents showed remarkable adsorption capacity and fast adsorption rate, mainly more than 88% of MB removal efficiency was reached after 50 min in 200 mg L-1 of dye solution. In addition, the incorporating of various content of clay has enhanced adsorption capacity of CTS-g-PAAm matrix from 1685 to a highest value of 1749 mg g-1 for the optimized nanocomposite containing 2 wt.% of MMt. The experimental kinetic data were well described by the pseudo-second-order model, while the equilibrium data were represented perfectly by Langmuir isotherm model. The maximum Langmuir equilibrium adsorption capacity (qm) was found to increase from 2173 mg g−1 until 2221 mg g−1 by adding 2 wt.% of clay nanofiller. Thermodynamic parameters revealed the spontaneous and endothermic nature of the process. In addition, the reusability study revealed that these bioadsorbents could be well regenerated with desorption efficiency overhead 87% and without any obvious decrease of removal efficiency as compared to starting ones even after four consecutive adsorption/desorption cycles, which exceeded 64%. These results suggest that the optimized nanocomposites are promising as low cost bioadsorbents.

Keywords: chitosan, clay, dye adsorption, hydrogels nanocomposites

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6063 Levels of Toxic Metals in Different Tissues of Lethrinus miniatus Fish from Arabian Gulf

Authors: Muhammad Waqar Ashraf, Atiq A. Mian

Abstract:

In the present study, accumulation of eight heavy metals, lead (Pb), cadmium (Cd), manganese (Mn), copper (Cu), zinc (Zn), iron (Fe), nickel (Ni) and chromium (Cr)was determined in kidney, heart, liver and muscle tissues of Lethrinus miniatus fish caught from Arabian Gulf. Metal concentrations in all the samples were measured using Atomic Absorption Spectroscopy. Analytical validation of data was carried out by applying the same digestion procedure to standard reference material (NIST-SRM 1577b bovine liver). Levels of lead (Pb) in the liver tissue (0.60µg/g) exceeded the limit set by European Commission (2005) at 0.30 µg/g. Zinc concentration in all tissue samples were below the maximum permissible limit (50 µg/g) as set by FAO. Maximum mean cadmium concentration was found 0.15 µg/g in the kidney tissues. Highest content of Mn in the studied tissues was seen in the kidney tissue (2.13 µg/g), whereas minimum was found in muscle tissue (0.87 µg/g). The present study led to the conclusion that muscle tissue is the least contaminated tissue in Lethrinus miniatus and consumption of organs should be avoided as much as possible.

Keywords: lethrinus miniatus, arabian gulf, heavy metals, atomic absorption spectroscopy

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6062 Laser - Ultrasonic Method for the Measurement of Residual Stresses in Metals

Authors: Alexander A. Karabutov, Natalia B. Podymova, Elena B. Cherepetskaya

Abstract:

The theoretical analysis is carried out to get the relation between the ultrasonic wave velocity and the value of residual stresses. The laser-ultrasonic method is developed to evaluate the residual stresses and subsurface defects in metals. The method is based on the laser thermooptical excitation of longitudinal ultrasonic wave sand their detection by a broadband piezoelectric detector. A laser pulse with the time duration of 8 ns of the full width at half of maximum and with the energy of 300 µJ is absorbed in a thin layer of the special generator that is inclined relative to the object under study. The non-uniform heating of the generator causes the formation of a broadband powerful pulse of longitudinal ultrasonic waves. It is shown that the temporal profile of this pulse is the convolution of the temporal envelope of the laser pulse and the profile of the in-depth distribution of the heat sources. The ultrasonic waves reach the surface of the object through the prism that serves as an acoustic duct. At the interface ‚laser-ultrasonic transducer-object‘ the conversion of the most part of the longitudinal wave energy takes place into the shear, subsurface longitudinal and Rayleigh waves. They spread within the subsurface layer of the studied object and are detected by the piezoelectric detector. The electrical signal that corresponds to the detected acoustic signal is acquired by an analog-to-digital converter and when is mathematically processed and visualized with a personal computer. The distance between the generator and the piezodetector as well as the spread times of acoustic waves in the acoustic ducts are the characteristic parameters of the laser-ultrasonic transducer and are determined using the calibration samples. There lative precision of the measurement of the velocity of longitudinal ultrasonic waves is 0.05% that corresponds to approximately ±3 m/s for the steels of conventional quality. This precision allows one to determine the mechanical stress in the steel samples with the minimal detection threshold of approximately 22.7 MPa. The results are presented for the measured dependencies of the velocity of longitudinal ultrasonic waves in the samples on the values of the applied compression stress in the range of 20-100 MPa.

Keywords: laser-ultrasonic method, longitudinal ultrasonic waves, metals, residual stresses

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6061 Field Evaluation of Different Aubergine Cultivars against Infestation of Brinjal Shoot and Fruit Borer

Authors: Ajmal Khan Kassi, Humayun Javed, Muhammad Asif Aziz

Abstract:

Response of different aubergine cultivars against Brinjal shoot and fruit borer (Leucinodes orbonalis Guenee.) was evaluated at research farm of PMAS, Arid Agriculture University, Rawalpindi, during 2013. Field trials were conducted in randomized completed block design with four replications for the screening of five cultivars of Brinjal (Solanum melongena L) (Short Purpal, Singhnath 666, Brinjal long 6275, Round Brinjal 86602, Round Egg Plant White). Cultivar Round White Brinjal showed maximum fruit infestation (54.44%) followed by Singhnath 666 (53.19%), while minimum fruit infestation was observed in Round Brinjal 86602 (42.39%). Cultivar Short Purpal showed maximum larval population (0.43) followed by Round White Brinjal (0.39), while the minimum larval population was observed in Round Brinjal 86602 with (0.27). It was observed that Round Brinjal 86602 cultivar showed comparatively minimum (L. orbonalis) larval population per leaf. The correlation of Brinjal fruit infestation and larval population of (L. orbonalis) with the different environmental factors showed that, the average relative humidity was positively and significantly correlated with fruit infestation on cultivars average precipitation showed positive but non- significant correlation on all the cultivars except Singhnath 666 with the value of (0.79) which was positive and significant. The average temperature showed non-significant and negative correlation with Brinjal long 6275, Round Brinjal 86602 and Singhnath 666, but significant negative correlation with Short Purpal and Round White Brinjal. Maximum temperature also showed the significant and negative correlation on all the five Brinjal cultivars which were significant and highly significant. Minimum temperature showed negative correlation and not significant correlation with all the cultivars. Consequently, based on the (L. orbonalis) larval density and Brinjal fruit infestation, the Round Brinjal 86602 proved least susceptible and Short Purpal highly susceptible cultivar.

Keywords: evaluation, Brinjal (Solanum melongena L), Cultivars, L. orbonalis

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