Search results for: Sidra Mahmood
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 188

Search results for: Sidra Mahmood

128 Levansucrase from Zymomonas Mobilis KIBGE-IB14: Production Optimization and Characterization for High Enzyme Yield

Authors: Sidra Shaheen, Nadir Naveed Siddiqui, Shah Ali Ul Qader

Abstract:

In recent years, significant progress has been made in discovering and developing new bacterial polysaccharides producing organisms possessing extremely functional properties. Levan is a natural biopolymer of fructose which is produced by transfructosylation reaction in the presence of levansucrase. It is one of the industrially promising enzymes that offer a variety of industrial applications in the field of cosmetics, foods and pharmaceuticals. Although levan has significant applications but the yield of levan produced is not equal to other biopolymers due to the inefficiency of producer microorganism. Among wide range of levansucrase producing microorganisms, Zymomonas mobilis is considered as a potential candidate for large scale production of this natural polysaccharide. The present investigation is concerned with the isolation of levansucrase producing natural isolate having maximum enzyme production. Furthermore, production parameters were optimized to get higher enzyme yield. Levansucrase was partially purified and characterized to study its applicability on industrial scale. The results of this study revealed that the bacterial strain Z. mobilis KIBGE-IB14 was the best producer of levansucrase. Bacterial growth and enzyme production was greatly influenced by physical and chemical parameters. Maximum levansucrase production was achieved after 24 hours of fermentation at 30°C using modified medium of pH-6.5. Contrary to other levansucrases, the one presented in the current study is able to produce high amount of products in relatively short period of time with optimum temperature at 35°C. Due to these advantages, this enzyme can be used on large scale for commercial production of levan and other important metabolites.

Keywords: levansucrase, metabolites, polysaccharides, transfructosylation

Procedia PDF Downloads 477
127 Mobile Application Testing Matrix and Challenges

Authors: Bakhtiar Amen, Sardasht Mahmood, Joan Lu

Abstract:

The adoption of smartphones and the usages of mobile applications are increasing rapidly. Consequently, within limited time-range, mobile Internet usages have managed to take over the desktop usages particularly since the first smartphone-touched application released by iPhone in 2007. This paper is proposed to provide solution and answer the most demandable questions related to mobile application automated and manual testing limitations. Moreover, Mobile application testing requires agility and physically testing. Agile testing is to detect bugs through automated tools, whereas the compatibility testing is more to ensure that the apps operates on mobile OS (Operation Systems) as well as on the different real devices. Moreover, we have managed to answer automated or manual questions through two mobile application case studies MES (Mobile Exam System) and MLM (Mobile Lab Mate) by creating test scripts for both case studies and our experiment results have been discussed and evaluated on whether to adopt test on real devices or on emulators? In addition to this, we have introduced new mobile application testing matrix for the testers and some enterprises to obtain knowledge from.

Keywords: mobile app testing, testing matrix, automated, manual testing

Procedia PDF Downloads 449
126 Using New Machine Algorithms to Classify Iranian Musical Instruments According to Temporal, Spectral and Coefficient Features

Authors: Ronak Khosravi, Mahmood Abbasi Layegh, Siamak Haghipour, Avin Esmaili

Abstract:

In this paper, a study on classification of musical woodwind instruments using a small set of features selected from a broad range of extracted ones by the sequential forward selection method was carried out. Firstly, we extract 42 features for each record in the music database of 402 sound files belonging to five different groups of Flutes (end blown and internal duct), Single –reed, Double –reed (exposed and capped), Triple reed and Quadruple reed. Then, the sequential forward selection method is adopted to choose the best feature set in order to achieve very high classification accuracy. Two different classification techniques of support vector machines and relevance vector machines have been tested out and an accuracy of up to 96% can be achieved by using 21 time, frequency and coefficient features and relevance vector machine with the Gaussian kernel function.

Keywords: coefficient features, relevance vector machines, spectral features, support vector machines, temporal features

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125 Using Axiomatic Design for Developing a Framework of Manufacturing Cloud Service Composition in the Equilibrium State

Authors: Ehsan Vaziri Goodarzi, Mahmood Houshmand, Omid Fatahi Valilai, Vahidreza Ghezavati, Shahrooz Bamdad

Abstract:

One important paradigm of industry 4.0 is Cloud Manufacturing (CM). In CM everything is considered as a service, therefore, the CM platform should consider all service provider's capabilities and tries to integrate services in an equilibrium state. This research develops a framework for implementing manufacturing cloud service composition in the equilibrium state. The developed framework using well-known tools called axiomatic design (AD) and game theory. The research has investigated the factors for forming equilibrium for measures of the manufacturing cloud service composition. Functional requirements (FRs) represent the measures of manufacturing cloud service composition in the equilibrium state. These FRs satisfied by related Design Parameters (DPs). The FRs and DPs are defined by considering the game theory, QoS, consumer needs, parallel and cooperative services. Ultimately, four FRs and DPs represent the framework. To insure the validity of the framework, the authors have used the first AD’s independent axiom.

Keywords: axiomatic design, manufacturing cloud service composition, cloud manufacturing, industry 4.0

Procedia PDF Downloads 151
124 Multi-Criteria Decision Support System for Modeling of Civic Facilities Using GIS Applications: A Case Study of F-11, Islamabad

Authors: Asma Shaheen Hashmi, Omer Riaz, Khalid Mahmood, Fahad Ullah, Tanveer Ahmad

Abstract:

The urban landscapes are being change with the population growth and advancements in new technologies. The urban sprawl pattern and utilizes are related to the local socioeconomic and physical condition. Urban policy decisions are executed mostly through spatial planning. A decision support system (DSS) is very powerful tool which provides flexible knowledge base method for urban planning. An application was developed using geographical information system (GIS) for urban planning. A scenario based DSS was developed to integrate the hierarchical muti-criteria data of different aspects of urban landscape. These were physical environment, the dumping site, spatial distribution of road network, gas and water supply lines, and urban watershed management, selection criteria for new residential, recreational, commercial and industrial sites. The model provided a framework to incorporate the sustainable future development. The data can be entered dynamically by planners according to the appropriate criteria for the management of urban landscapes.

Keywords: urban, GIS, spatial, criteria

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123 Evaluation of Wound Healing Activity of Curcuma purpurascens BI. Rhizomes in Rats

Authors: Elham Rouhollahi, Soheil Zorofchian Moghadamtousi, Salma Baig, Mahmood Ameen Abdulla, Zahurin Mohamed

Abstract:

This study was designed to assess cutaneous wound healing potential of hexane extract of Curcuma purpurascens rhizomes (HECP). Twenty-four rats were divided into 4 groups: 1. Negative, 2. Low dose, 3. High dose and 4. Treatment, with 6 rats in each group. Full-thickness incisions with a diameter of 2 cm were made on the back of each rat. Rats were topically treated two times a day for 15 days. Group 1-4 were treated with sterile distilled water, 5% and 10% of extract and intrasite gel, respectively. Masson's trichrome and hematoxylin staining techniques are employed for histological analysis revealed strong wound healing potential closer to that of conventional drug intrasite gel. HECP significantly decreased wound area and an increase in hydroxyproline, cellular proliferation, the number of blood vessels and the level of collagen synthesis was observed. Thus, it could be concluded that HECP possesses strong wound healing potential.

Keywords: Curcuma purpurascens, wound healing, histopathology, hematoxylin staining

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122 Computer Aided Screening of Secreted Frizzled-Related Protein 4 (SFRP4): A Potential Control for Diabetes Mellitus

Authors: Shazia Anwer Bukhari, Waseem Akhtar Shamshari, Mahmood-Ur-Rahman, Muhammad Zia-Ul-Haq, Hawa Z. E. Jaafar

Abstract:

Diabetes mellitus is a life threatening disease and scientists are doing their best to find a cost effective and permanent treatment of this malady. The recent trend is to control the disease by target base inhibiting of enzymes or proteins. Secreted frizzled-related protein 4 (SFRP4) is found to cause five times more risk of diabetes when expressed above average levels. This study was therefore designed to analyze the SFRP4 and to find its potential inhibitors. SFRP4 was analyzed by bio-informatics tools of sequence tool and structure tool. A total of three potential inhibitors of SFRP4 were found, namely cyclothiazide, clopamide and perindopril. These inhibitors showed significant interactions with SFRP4 as compared to other inhibitors as well as control (acetohexamide). The findings suggest the possible treatment of diabetes mellitus type 2 by inhibiting the SFRP4 using the inhibitors cyclothiazide, clopamide and perindopril.

Keywords: bioscreening, clopamide, cyclothiazide, diabetes mellitus, perindopril, SFRP4

Procedia PDF Downloads 418
121 Influence of Single Source Irradiation on the Homogeneous Alignment of Liquid Crystals Molecules on Glass Substrates

Authors: Sarah Akhtar, Rizwan Mahmood

Abstract:

A detailed study of homogeneous alignment of liquid crystal molecules on a glass substrate will be presented. Thin films of polyimide were coated on several glass substrates. Various methods were employed to prepare coated surfaces to achieve desired alignment; these include traditionally rubbing the surface with a felt cloth then exposing them perpendicular to the easy axis with incandescent light (IL), linearly polarized ultraviolet (LPUVR) and un-polarized ultraviolet (UPUVR) radiation. The quality of the alignment was tested by measuring the tilt angle in the temperature range between 30°C to 55°C. Regression analysis of the data using ‘SigmaPlot’ suggests a gradual increase in tilt angle (1.1°-1.8°) for the rubbed, 0.6° to 3.6° increase for the rubbed plus IL radiated and 1.6° to 4.6° for the rubbed plus UPUVL radiated samples, respectively. However to our surprise, we found tilt angle to be decreasing from 2.4° to 1.6° for the rubbed plus LPUVL radiated samples. We hope that these findings will be helpful in the fabrication of display panels and other electro-optic devices.

Keywords: homogeneous, liquid crystals, polyimide, tilt angle

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120 New Quinazoline Derivative Induce Cytotoxic Effect against Mcf-7 Human Breast Cancer Cell

Authors: Maryam Zahedi Fard, Nazia Abdul Majid, Hapipah Mohd Ali, Mahmood Ameen Abdulla

Abstract:

New quinazoline schiff base 3-(5-bromo-2-hydroxy-3-methoxybenzylideneamino)-2-(5-bromo-2-hydroxy-3-methoxyphenyl)-2,3-dihydroquinazolin-4(1H)-one was investigated for anticancer activity against MCF-7 human breast cancer cell line with involved mechanism of apoptosis. The compound demonstrated a remarkable antiproliferative effect, with an IC50 value of 3.41 ± 0.34, after 72 hours of treatment. Morphological apoptotic features in treated MCF-7 cells were observed by AO/PI staining. Furthermore, treated MCF-7 cells subjected to apoptosis death, as exhibited by perturbation of mitochondrial membrane potential and cytochrome c release as well as increase in ROS generation. We also found activation of caspases 3/7 and -9. Moreover, acute toxicity test demonstrated the nontoxic nature of the compound in mice. Our results showed the selected compound significantly induce apoptosis in MCF-7 cells via intrinsic pathway, which might be considered as a potent candidate for further in vivo and clinical breast cancer studies.

Keywords: antiproliferative effect, MCF-7 human breast cancer cell line, apoptosis, caspases

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119 Detection of Leishmania Mixed Infection from Phlebotomus papatasi in Central Iran

Authors: Nassibeh Hosseini-Vasoukolaei, Amir Ahmad Akhavan, Mahmood Jeddi-Tehrani, Ali Khamesipour, Mohammad Reza Yaghoobi Ershadi, Kamhawi Shaden, Valenzuela Jesus, Hossein Mirhendi, Mohammad Hossein Arandian

Abstract:

Zoonotic cutaneous leishmaniasis (ZCL) is an endemic disease in many rural areas of Iran. Sand flies were collected from rural areas of Esfahan province and were identified using valid identification keys. DNA was extracted from sand flies and Nested PCRs were done using specific primers. In this study, 44 out of 152 (28.9 %) sand flies were infected with L. majoralone. Eight sand flies showed mixed infection: four sand flies (2.6 %) were infected with L. major, L. turanicaand L. gerbili, one sand fly (0.7 %) was infected with L. major and L. turanica and three sand flies (2 %) were infected with L. turanicaand L. gerbili. Our results demonstrate the natural infection of P. papatasi sand fly with three species of L. major, L. turanica and L. gerbili which are circulating among R. opimusreservoir host and P. papatasi sand fly vector in central Iran.

Keywords: Phlebotomus papatasi, Leishmania major, Leishmania turanica, Leishmania gerbili, mixed infection, Iran

Procedia PDF Downloads 444
118 Knowledge Management and Motivation Management: Important Constituents of Firm Performance

Authors: Yassir Mahmood, Nadia Ehsan

Abstract:

In current research stream, empirical work regarding knowledge and motivation management along their dimensions is sparse. This study partially filled this void by investigating the influence of knowledge management (tacit and explicit) and motivation management (intrinsic and extrinsic) on firm performance with the mediating effects of innovative performance. Based on the quantitative research method, data were collected through questionnaire from 284 employees working in 18 different firms across the citrus industry located in Sargodha region (Pakistan). The proposed relationships were tested through regression analysis while mediation relations were analyzed through Barron and Kenny (1986) technique. The results suggested that knowledge management (KM) and motivation management (MM) have significant positive impacts on innovative performance (IP). In addition, the role of IP as full mediator between KM and firm performance (FP) is confirmed. Also, IP proved to be a partial mediator between MM and FP. From the managerial perspective, the findings of the study are vital as some of the important constituents of FP have been highlighted. The study produced important underpinnings for managers. In last, implications for policymakers along with future research directions are discussed.

Keywords: innovative performance, firm performance, knowledge management, motivation management, Sargodha

Procedia PDF Downloads 128
117 Unreality of Real: Debordean Reading of Gillian Flynn's Gone Girl

Authors: Sahand Hamed Moeel Ardebil, Zohreh Taebi Noghondari, Mahmood Reza Ghorban Sabbagh

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Gillian Flynn’s Gone Girl, depicts a society in which, as a result of media dominance, the reality is very precarious and difficult to grasp. In Gone Girl, reality and image of reality represented on TV, are challenging to differentiate. Along with reality, individuals’ agency and independence before media and the capitalist rule are called in to question in the novel. In order to expose the unstable nature of reality and an individual’s complicated relationship with media, this study has deployed the ideas of Marxist-media theorist Guy Debord (1931-1992). In his book Society of the Spectacle (1966), Debord delineates a society in which images replace the objective reality, and people are incapable of making real changes. The results of the current study show that despite their efforts, Nick and Amy, the two main characters of the novel, are no more than spectators with very little agency before the media. Moreover, following Debord’s argument about the replacement of reality with images, everyone and every institution in Gone Girl projects an image that does not necessarily embody the objective reality, a fact that makes it very hard to differentiate the real from unreal.

Keywords: agency, Debord, Gone Girl, media studies, society of spectacle, reality

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116 Wave Propagation In Functionally Graded Lattice Structures Under Impact Loads

Authors: Mahmood Heshmati, Farhang Daneshmand

Abstract:

Material scientists and engineers have introduced novel materials with complex geometries due to the recent technological advances and promotion of manufacturing methods. Among them, lattice structures with graded architectures denoted by functionally graded porous materials (FGPMs) have been developed to optimize the structural response. FGPMs are achieved by tailoring the size and density of the internal pores in one or more directions that lead to the desired mechanical properties and structural responses. Also, FGPMs provide more flexible transition and the possibility of designing and fabricating structural elements with complex and variable properties. In this paper, wave propagation in lattice structures with functionally graded (FG) porosity is investigated in order to examine the ability of shock absorbing effect. The behavior of FG porous beams with different porosity distributions under impact load and the effects of porosity distribution and porosity content on the wave speed are studied. Important conclusions are made, along with a discussion of the future scope of studies on FGPMs structures.

Keywords: functionally graded, porous materials, wave propagation, impact load, finite element

Procedia PDF Downloads 56
115 Islamic Banks and the Most Important Contemporary Challenges

Authors: Mahmood Mohammed Abdulsattar Aljumaili

Abstract:

Praise be to Allah and peace and blessings be upon the Messenger of Allah. Islamic banks have not only made a lot of great achievements in a short period, but they imposed themselves in the global market, not to mention the transformation of some conventional interest-based banks to Islamic banks to the large demand on them, this transformation has pushed the Dow Jones Global Foundation to develop a new economic indicator released it (the Dow Jones Islamic market) for those who wish to invest in Islamic financial institutions. The success of Islamic financial institutions today face significant and serious challenges, that embody the serious consequences created by the current events on Islamic banking industry. This modest study, deals with these serious challenges facing the Islamic banking industry, and reflected on the success recorded in the previous period. The study deals with four main topics: The emergence of Islamic banks, the goals of Islamic banks, International challenges facing Islamic banks, internal challenges facing Islamic banks, and finally it touches on, (Basel 1-2) Agreement and its implications for Islamic banks.

Keywords: Islamic banks, Basel 1-2 agreement, most important contemporary challenges, islamic banking industry, Dow Jones Islamic market

Procedia PDF Downloads 473
114 Awareness, Use and Searching Behavior of 'Virtua' Online Public Access Catalog Users

Authors: Saira Soroya, Khalid Mahmood

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Library catalogs open the door to the library collection. OPAC (Online Public Access Catalog) are one of the services offered by automated libraries. The present study aims to explore user’s awareness, the level of use and their searching behavior of OPAC with a purpose to give suggestions and ways to improve user-friendly features of library OPAC. The population consisted of OPAC users of Lahore University of Management Sciences (LUMS). Convenient sampling technique was carried out. Total sample size was 100 OPAC users. Quantitative research design, based on survey method used to carry out the study. The data collection instrument was adopted. Data was analyzed using SPSS. Results revealed that a considerable number of users were not aware of OPAC i.e. (30%); however, those who were aware were using basic features of the OPAC. It was found that lack of knowledge was considered the frequent reason for not using all features of OPAC. In this regard, it is strongly recommended that compulsory information literacy programme should be established.

Keywords: catalog, OPAC, library automation, usability study, university library

Procedia PDF Downloads 310
113 Bilateral Trade Costs Analysis of Policy Barriers for Growth Oriented Strategies in Exports

Authors: Shabana Noureen, Zafar Mahmood

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Economies consistently engage in trade across borders and face tariff, non-tariff barriers and other quotas that constitute trade costs. The trade costs imposed by policy barriers on exports are considered an impediment in the export growth rate. This work aims to measure over-year trends in total and bilateral trade costs and their trends in relevance to policy barriers (tariff and non-tariff). The analysis through the micro-founded theoretically based gravity model showed that the total trade costs have a general decreasing trend in the world while in the case of developing countries, the rate by which these trends decline is very low. Bilateral trade cost estimates associated with the policy barriers represent that the non-tariff barriers in a developing country have a major role in sustaining the high trade costs as compared to the tariff barriers. This ultimately leads to a low net declining rate. This work emphasizes that for developing countries the non-tariff barriers are a major factor that renders their exports and to be uncompetitive in the world market.

Keywords: trade costs, policy barriers, tariff barriers, non-tariff barriers, trade policies, export growth

Procedia PDF Downloads 227
112 Pakistan’s Taxation System: A Critical Appraisal

Authors: Khalid Javed, Rashid Mahmood

Abstract:

The constitution empowers the Federal Government to collect taxes on income other than agricultural income, taxes on capital value, customs, excise duties and sales taxes. The Central Board of Revenue (CBR) and its subordinate departments administer the tax system. Each of the three principal taxes has a different history and different set of issues. For a large number of income tax payers the core of the business process is pre-audit and assessment by a tax official. This process gives considerable discretion to tax officials, with potential for abuse. Moreover, this process is also not tenable as the number of taxpayers increase. The report is focused on a total overhaul of the process and organization of income tax. Sales tax is recent and its process and organization is adjusted to the needs of an expanding tax base. These are based on self-assessment and selective audit. Similarly, in customs the accent is on accelerating and broadening the changes begun in recent years. Before long, central excise will be subsumed in sales tax. During the nineties, despite many changes in the tax regime and introduction of withholding and presumptive taxes, Federal Government tax to GDP ratio has varied narrowly around eleven percent. The tax base has grown but still remains narrow and skewed. The number of income tax filers is around one million.

Keywords: central board of revenue, GDP, sale tax, income tax

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111 The Environment in Urban Planning and Management

Authors: Mahmood Salahi, Fatemeh Abbasi

Abstract:

Increasing urbanization will be one of the defining features of the 21st century. This produces particular environmental challenges, but also creates opportunities for urban development that can contribute to broader goals of improving the quality of life for urban residents while achieving greater levels of global sustainability. Half of the world’s population already lives in urban areas, with a growing number of these people living in towns and cities in low and middle-income countries. As well as being a demographic phenomenon, urbanisation is intricately linked with economic, social and environmental transitions. The increasing proportion of the world’s population living in urban areas has been driven by the growing concentration of new investment and employment opportunities. In general, nations with the most rapid and sustained economic growth have urbanized most.2 Urban centres provide opportunities for a range of social and cultural activities, as well as being critical for innovations in science, technology and education. Indeed, urban areas are of critical importance for social and economic development: as the Cities Alliance recognizes, 'only sustained urban growth has the capacity to lift both rural and urban populations out of poverty'.

Keywords: environment, urban planning, management, urbanization

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110 Enhancement in Seebeck Coefficient of MBE Grown Un-Doped ZnO by Thermal Annealing

Authors: M. Asghar, K. Mahmood, F. Malik, Lu Na, Y-H Xie, Yasin A. Raja, I. Ferguson

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In this paper, we have reported an enhancement in Seebeck coefficient of un-doped zinc oxide (ZnO) grown by molecular beam epitaxy (MBE) on silicon (001) substrate by annealing treatment. The grown ZnO thin films were annealed in oxygen environment at 500°C – 800°C, keeping a step of 100°C for one hour. Room temperature Seebeck measurements showed that Seebeck coefficient and power factor increased from 222 to 510 µV/K and 8.8×10^-6 to 2.6×10^-4 Wm^-1K^-2 as annealing temperature increased from 500°C to 800°C respectively. This is the highest value of Seebeck coefficient ever reported for un-doped MBE grown ZnO according to best of our knowledge. This observation was related with the improvement of crystal structure of grown films with annealing temperature. X-ray diffraction (XRD) results demonstrated that full width half maximum (FWHM) of ZnO (002) plane decreased and crystalline size increased as the annealing temperature increased. Photoluminescence study revealed that the intensity of band edge emission increased and defect emission decreased as annealing temperature increased because the density of oxygen vacancy related donor defects decreased with annealing temperature. This argument was further justified by the Hall measurements which showed a decreasing trend of carrier concentration with annealing temperature.

Keywords: ZnO, MBE, thermoelectric properties, annealing temperature, crystal structure

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109 Mutagenicity Evaluation of Locally Produced Biphasic Calcium Phosphate Using Ames Test

Authors: Nur Fathin Alia Che Wahab, Thirumulu Ponnuraj Kannan, Zuliani Mahmood, Ismail Ab. Rahman, Hanafi Ismail

Abstract:

Locally produced Biphasic Calcium Phosphate (BCP) consists of hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) which is a promising material for dentin and bone regeneration as well as in tissue engineering applications. The study was carried out to investigate the mutagenic effect of locally produced BCP using Ames test. Mutagenicity was evaluated with and without the addition of metabolic activation system (S9). This study was performed on Salmonella typhimurium TA98, TA102, TA1537, and TA1538 strains using preincubation assay method. The doses tested were 5000, 2500, 1250, 625, 313 µg/plate. Negative and positive controls were also included. The bacteria were incubated for 48 hours at 37 ± 0.5 °C. Then, the revertant colonies were counted. Data obtained were evaluated using non-statistical method. The mean number of revertant colonies in strains with and without S9 mix treated with locally produced BCP was less than double when compared to negative control for all the tested concentrations. The results from this study indicate that the locally produced BCP is non-mutagenic under the present test conditions.

Keywords: ames test, biphasic calcium phosphate, dentin regeneration, mutagenicity

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108 Investigating the Flavin-Dependent Thymidylate Synthase (FDTS) Enzyme from Clostridioides Difficile (C. diff)

Authors: Sidra Shaw, Sarenna Shaw, Chae Joon Lee, Irimpan Mathews, Eric Koehn

Abstract:

One of the biggest public health concerns of our time is increasing antimicrobial resistance. As of 2019, the CDC has documented more than 2.8 million serious antibiotic resistant infections in the United States. Currently, antibiotic resistant infections are directly implicated in over 750,000 deaths per year globally. On our current trajectory, British economist Jim O’Neill predicts that by 2050, an additional 10 million people (about half the population of New York) will die annually due to drug resistant infections. As a result, new biochemical pathways must be targeted to generate next generation antibiotic drugs that will be effective against drug resistant bacteria. One enticing target is the biosynthesis of DNA within bacteria, as few drugs interrupt this essential life process. Thymidylate synthase enzymes are essential for life as they catalyze the synthesis of a DNA building block, 2′-deoxythymidine-5′-monophosphate (dTMP). In humans, the thymidylate synthase enzyme (TSase) has been shown to be distinct from the flavin-dependent thymidylate synthase (FDTS) produced by many pathogenic bacteria. TSase and FDTS have distinct structures and mechanisms of catalysis, which should allow selective inhibition of FDTS over human TSase. Currently, C. diff is one of the most antibiotic resistant bacteria, and no drugs that target thymine biosynthesis exist for C. diff. Here we present the initial biochemical characterization of FDTS from C. diff. Specifically, we examine enzyme kinetics and binding features of this enzyme to determine the nature of interaction with ligands/inhibitors and understand the molecular mechanism of catalysis. This research will provide more insight into the targetability of the C. diff FDTS enzyme for novel antibiotic drugs.

Keywords: flavin-dependent thymidylate synthase, FDTS, clostridioides difficile, C. diff, antibiotic resistance, DNA synthesis, enzyme kinetics, binding features

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107 Modeling Dynamics and Control of Transversal Vibration of an Underactuated Flexible Plate Using Controlled Lagrangian Method

Authors: Mahmood Khalghollah, Mohammad Tavallaeinejad, Mohammad Eghtesad

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The method of Controlled Lagrangian is an energy shaping control technique for under actuated Lagrangian systems. Energy shaping control design methods are appealing as they retain the underlying nonlinear dynamics and can provide stability results that hold over larger domain than can be obtained using linear design and analysis. In the present study, controlled lagrangian is employed for designing a controller in an under actuated rotating flexible plate system. In the system of rotating flexible plate, due to its nonlinear characteristics and coupled dynamics of rigid and flexible components, controller design is a known challenge. In this paper, controller objectives are considered to be vibration reduction of flexible component and position control of the tip of the plate. To achieve the goals, a method based on both kinetic and potential energy shaping is introduced. The stability of the closed-loop system is investigated and proved around its equilibrium points. Moreover, the proposed controller is shown to be robust against disturbance and plant uncertainties.

Keywords: controlled lagrangian, underactuated system, flexible rotating plate, disturbance

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106 Molecular Dynamics Simulation of Free Vibration of Graphene Sheets

Authors: Seyyed Feisal Asbaghian Namin, Reza Pilafkan, Mahmood Kaffash Irzarahimi

Abstract:

TThis paper considers vibration of single-layered graphene sheets using molecular dynamics (MD) and nonlocal elasticity theory. Based on the MD simulations, Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS), an open source software, is used to obtain fundamental frequencies. On the other hand, governing equations are derived using nonlocal elasticity and first order shear deformation theory (FSDT) and solved using generalized differential quadrature method (GDQ). The small-scale effect is applied in governing equations of motion by nonlocal parameter. The effect of different side lengths, boundary conditions and nonlocal parameter are inspected for aforementioned methods. Results are obtained from MD simulations is compared with those of the nonlocal elasticity theory to calculate appropriate values for the nonlocal parameter. The nonlocal parameter value is suggested for graphene sheets with various boundary conditions. Furthermore, it is shown that the nonlocal elasticity approach using classical plate theory (CLPT) assumptions overestimates the natural frequencies.

Keywords: graphene sheets, molecular dynamics simulations, fundamental frequencies, nonlocal elasticity theory, nonlocal parameter

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105 A Survey on Early Screen Exposure during Infancy and Autism

Authors: I. Mahmood

Abstract:

This survey was conducted to explore the hypothesis that excessive screen exposure combined with a subsequent decrease in parent-child interaction during infancy might be associated with autism. The main questions being asked are: Were children with autism exposed to long hours of screen time during the first 2 years of life? And what was the reason(s) for exposure at such an early age? Other variables were also addressed in this survey. An Arabic questionnaire was administered online (June 2019) via a Facebook page, relatively well-known in Arab countries. 1725 parents of children diagnosed with autism participated in this survey. Results show that 80.9% of children surveyed who were diagnosed with autism had been exposed to screens for long periods of time during the first 2 years of life. It can be inferred from the results of this survey that over-exposure to screens disrupt the parent-child interaction which is shown to be associated with ASD. The results of this survey highlight the harmful effects of screen exposure during infancy and the importance of parent-child interaction during the critical period of brain development. This paper attempts to further explore the connection between parent-child interaction and ASD, as well as serve as a call for further research and investigation of the relation between screens and parent-child interactions during infancy and Autism.

Keywords: attachment disorder, autism, screen exposure, virtual autism

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104 Framework for Implementation of National Electrical Safety Grounding Standards for Communication Infrastructure

Authors: Atif Mahmood, Mohammad Inayatullah Khan Babar

Abstract:

Communication infrastructure has been installed, operated, and maintained all over the world according to defined electrical safety standards for separate or joint structures. These safety standards have been set for the safeguard of public, utility workers (employees and contractors), utility facilities, electrical communication equipment’s connected to the utility facilities and other facilities or premise adjacent to utility facilities. Different communication utilities in Pakistan use standards of different countries due to the absence of Common National Electrical Safety Standards of Pakistan. It is really important to devise a framework for implementation of a uniform standard for strict compliance. In this context, it is important to explore the compliance of safety standards for communication conductors and equipment for separate or joint structures for which NESC standards are taken as reference. Specific reference to grounding techniques including grounding AC/DC systems and its frames, leaving Fences, Messenger wires and special circuits used for the protection for lightning etc, ungrounded so recommendations are also given after in-depth analysis of current technical practices for the installation and maintenance of communication infrastructure.

Keywords: utility facilities, grounding electrodes, special circuits, grounding conductor

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103 Development of a Highly Flexible, Sensitive and Stretchable Polymer Nanocomposite for Strain Sensing

Authors: Shaghayegh Shajari, Mehdi Mahmoodi, Mahmood Rajabian, Uttandaraman Sundararaj, Les J. Sudak

Abstract:

Although several strain sensors based on carbon nanotubes (CNTs) have been reported, the stretchability and sensitivity of these sensors have remained as a challenge. Highly stretchable and sensitive strain sensors are in great demand for human motion monitoring and human-machine interface. This paper reports the fabrication and characterization of a new type of strain sensors based on a stretchable fluoropolymer / CNT nanocomposite system made via melt-mixing technique. Electrical and mechanical characterizations were obtained. The results showed that this nanocomposite sensor has high stretchability up to 280% of strain at an optimum level of filler concentration. The piezoresistive properties and the strain sensing mechanism of the strain sensor were investigated using Electrochemical Impedance Spectroscopy (EIS). High sensitivity was obtained (gauge factor as large as 12000 under 120% applied strain) in particular at the concentrations above the percolation threshold. Due to the tunneling effect, a non- linear piezoresistivity was observed at high concentrations of CNT loading. The nanocomposites with good conductivity and lightweight could be a promising candidate for strain sensing applications.

Keywords: carbon nanotubes, fluoropolymer, piezoresistive, strain sensor

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102 Assessment of Radiological Dose for Th-232 Laboratory Accumulated in Tropical Freshwater Fish

Authors: Zal U’yun Wan Mahmood, Norfaizal Mohamed, Nita Salina Abu Bakar, Yii Mei Wo, Abdul Kadir Ishak, Mohamad Noh Sawon, Mohd Tarmizi Ishak, Khairul Nizam Razali

Abstract:

The study of thorium radiotracer bioaccumulation in the whole body tropical freshwater fish (Anabas testudeneus; climb pearch) was performed. The objective of this study was to evaluate the effect of different Th-232 activity concentration andradiological dose in Anabas testudeneus under the laboratory bioaccumulation condition. Anabas testudeneus adults were exposed to different waterborne Th-232 levels: 0 BqL-1 (control), 50 BqL-1, 100 BqL-1,150 BqL-1and 200 BqL-1for 30 days. Radionuclide concentration ratios between the whole body levels and water levels were calculated and; total dose rates and risk quotients using ERICA Assessment Tool were also estimated. The results showed the increase of waterborne Th-232 concentration corresponded to a progressive decrease of Th concentration ratio. Meanwhile, the total dose rate (internal and external) in the whole body of Anabas testudeneus less than the ERICA dose rate screening value of 10 µGyh-1 and the risk quotient less than one. Thus, the findings can be concluded that the radiological dose of Th-232 to Anabas testudeneus is a very low probability and the situation may be considered to be of negligible radiological concern.

Keywords: Anabas testudeneus, bioaccumulation, radiological dose, Th-232

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101 Taleghan Dam Break Numerical Modeling

Authors: Hamid Goharnejad, Milad Sadeghpoor Moalem, Mahmood Zakeri Niri, Leili Sadeghi Khalegh Abadi

Abstract:

While there are many benefits to using reservoir dams, their break leads to destructive effects. From the viewpoint of International Committee of Large Dams (ICOLD), dam break means the collapse of whole or some parts of a dam; thereby the dam will be unable to hold water. Therefore, studying dam break phenomenon and prediction of its behavior and effects reduces losses and damages of the mentioned phenomenon. One of the most common types of reservoir dams is embankment dam. Overtopping in embankment dams occurs because of flood discharge system inability in release inflows to reservoir. One of the most important issues among managers and engineers to evaluate the performance of the reservoir dam rim when sliding into the storage, creating waves is large and long. In this study, the effects of floods which caused the overtopping of the dam have been investigated. It was assumed that spillway is unable to release the inflow. To determine outflow hydrograph resulting from dam break, numerical model using Flow-3D software and empirical equations was used. Results of numerical models and their comparison with empirical equations show that numerical model and empirical equations can be used to study the flood resulting from dam break.

Keywords: embankment dam break, empirical equations, Taleghan dam, Flow-3D numerical model

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100 Model Based Fault Diagnostic Approach for Limit Switches

Authors: Zafar Mahmood, Surayya Naz, Nazir Shah Khattak

Abstract:

The degree of freedom relates to our capability to observe or model the energy paths within the system. Higher the number of energy paths being modeled leaves to us a higher degree of freedom, but increasing the time and modeling complexity rendering it useless for today’s world’s need for minimum time to market. Since the number of residuals that can be uniquely isolated are dependent on the number of independent outputs of the system, increasing the number of sensors required. The examples of discrete position sensors that may be used to form an array include limit switches, Hall effect sensors, optical sensors, magnetic sensors, etc. Their mechanical design can usually be tailored to fit in the transitional path of an STME in a variety of mechanical configurations. The case studies into multi-sensor system were carried out and actual data from sensors is used to test this generic framework. It is being investigated, how the proper modeling of limit switches as timing sensors, could lead to unified and neutral residual space while keeping the implementation cost reasonably low.

Keywords: low-cost limit sensors, fault diagnostics, Single Throw Mechanical Equipment (STME), parameter estimation, parity-space

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99 Cross-Linked Amyloglucosidase Aggregates: A New Carrier Free Immobilization Strategy for Continuous Saccharification of Starch

Authors: Sidra Pervez, Afsheen Aman, Shah Ali Ul Qader

Abstract:

The importance of attaining an optimum performance of an enzyme is often a question of devising an effective method for its immobilization. Cross-linked enzyme aggregate (CLEAs) is a new approach for immobilization of enzymes using carrier free strategy. This method is exquisitely simple (involving precipitation of the enzyme from aqueous buffer followed by cross-linking of the resulting physical aggregates of enzyme molecules) and amenable to rapid optimization. Among many industrial enzymes, amyloglucosidase is an important amylolytic enzyme that hydrolyzes alpha (1→4) and alpha (1→6) glycosidic bonds in starch molecule and produce glucose as a sole end product. Glucose liberated by amyloglucosidase can be used for the production of ethanol and glucose syrups. Besides this amyloglucosidase can be widely used in various food and pharmaceuticals industries. For production of amyloglucosidase on commercial scale, filamentous fungi of genera Aspergillus are mostly used because they secrete large amount of enzymes extracellularly. The current investigation was based on isolation and identification of filamentous fungi from genus Aspergillus for the production of amyloglucosidase in submerged fermentation and optimization of cultivation parameters for starch saccharification. Natural isolates were identified as Aspergillus niger KIBGE-IB36, Aspergillus fumigatus KIBGE-IB33, Aspergillus flavus KIBGE-IB34 and Aspergillus terreus KIBGE-IB35 on taxonomical basis and 18S rDNA analysis and their sequence were submitted to GenBank. Among them, Aspergillus fumigatus KIBGE-IB33 was selected on the basis of maximum enzyme production. After optimization of fermentation conditions enzyme was immobilized on CLEA. Different parameters were optimized for maximum immobilization of amyloglucosidase. Data of enzyme stability (thermal and Storage) and reusability suggested the applicability of immobilized amyloglucosidase for continuous saccharification of starch in industrial processes.

Keywords: aspergillus, immobilization, industrial processes, starch saccharification

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